The Ultimate Guide to Woodlouse Names: Discover Their Quirky Nicknames

Few creatures have collected as many nicknames as the humble woodlouse. Surveys by the University of Edinburgh and others have recorded somewhere between 250 and 300 traditional names across the British Isles alone — woodlouse, slater, chucky pig, cheese-log, monkey pea, granny grey and many more — with what you call them depending almost entirely on where you grew up. This guide explores that rich tapestry of regional names: how they cluster into families, what they reveal about language and folklore, and why so many are quietly disappearing.

The main name groups we'll cover are the standard terms (woodlouse, slater), pig-related names (chucky pig, sow bug, penny sow), cheese and food names (cheesy bob, cheese bug), grandparent names (granny grey, granfer grey), borrowed insect names (forky-tailer, monkey-pede), and a scattering of rare regional oddities.

What Is a Woodlouse? (And Why the Name Confuses)

"Woodlouse" is the standard modern English name for the small, grey, segmented terrestrial isopods of the suborder Oniscidea. Despite their bug-like look, they aren't insects at all — they're crustaceans, more closely related to crabs and shrimp than to beetles or spiders. They have seven pairs of jointed legs, breathe through gill-like structures sometimes called pleopodal lungs, and feed on decaying matter as important garden detritivores. The "louse" part is misleading: unlike true lice, woodlice aren't parasitic, and their anatomy is thoroughly crustacean.

Their history runs deep. Marine isopods colonised land during the Carboniferous period, roughly 359 to 299 million years ago, and fossil woodlice clearly recognisable as terrestrial species appear in mid-Cretaceous amber around 100 million years old. Scientists have described roughly 3,710 woodlouse species worldwide, with estimates of perhaps 5,000 to 7,000 in total. The UK's most familiar species, the common pill bug Armadillidium vulgare, is just one of them — though to most people a woodlouse is simply a woodlouse, whatever the species.

How Many Names Do Woodlice Have?

The sheer count is extraordinary. Research by Warren Maguire and Tamsin Blaxter at the University of Edinburgh, gathering traditional names through dialect surveys across Scotland, England, Wales and Ireland, found around 250 distinct names in Scottish-focused surveys alone, with broader UK and Irish mapping identifying over 300 separate terms. An older popular-science figure of "176 nicknames" is often quoted, but appears to be a more conservative earlier count.

Many of these "different" names are really local variants of the same base word. The pig family shows this neatly: chucky pig, chuggy pig, chicky pig, chiggy pig and chiggy wig are mostly pronunciation shifts of a single idea. Even so, the genuine diversity is substantial, and the names sort into recognisable themed families: pigs and sows, cheese and food, grandparents and family, borrowed bug names, and personal names. Understanding those categories makes the whole bewildering variety far easier to navigate.

Standard Names: Woodlouse and Slater

A handful of names dominate, and increasingly they're the only ones younger speakers recognise. Woodlouse is the most common modern term, appearing in roughly 40–45% of UK and Irish survey responses and especially standard in England, Wales and the Republic of Ireland. The etymology is simple: the creatures turn up in old wood, and their segmented bodies were thought to resemble lice — a name based on habitat and appearance rather than biology.

Slater is the main rival, accounting for about a quarter of responses and dominant in Scotland and Northern Ireland, with forms like "slatey" or "slate-back" in some areas. It likely connects to slate or stone — the damp surfaces where woodlice gather — or possibly an older word for grey. Both standard terms are steadily replacing older local nicknames, driven by media, education and national standardisation, with woodlouse gaining ground among the young even in slater's heartlands.

Pig and "Chucky Pig" Names

A large share of dialect names link woodlice to pigs — pig, sow, hog and grunt all appear — probably inspired by their rounded bodies and rooting, foraging movement through leaf litter. It's an intuitive comparison that seems to have arisen independently in many communities.

The chucky pig cluster is one of the most distinctive in British dialectology, concentrated in south-west England around Bath, Bristol and Devon. The main variants and their strongholds are: chucky pig (Bristol and Bath), chookie pig (Somerset), chuggy pig (Devon), chicky pig (North Devon), and chiggy pig and chiggy wig (scattered across the south-west and Devon). The "chucky" element may echo traditional pig-calling cries, and these names are typically learned in childhood, passed down through family and playground rather than school.

Other pig-related forms are tied to particular places: parson's pig (Isle of Man), fat pig (around Cork, Ireland), penny sow (Pembrokeshire, Wales), sow bug (the Cambridgeshire–Essex–Hertfordshire corridor), sow pigs (scattered across East Anglia), and wood pig (various). Taken together, porcine names make up roughly a fifth (about 19%) of all recorded woodlouse names — the second-largest category after the standard terms, and a sign of how deeply the pig association is rooted in rural British and Irish culture, especially for the rounded, ball-rolling "pill" woodlice found under stones and logs.

Cheese, Grandmothers and Other Themed Nicknames

Beyond pigs, many names draw on playful images — food, elderly relatives, even personal names.

Cheese names concentrate in southern England, with "cheese-log" and "cheesy bob" the most commonly recorded and "cheese bug" overlapping. Related historical forms like "cheslop" or "chestlokes" are attested from the 1500s, so the cheese idea has real antiquity. Dialect maps even suggest a drift over time, with older cheese-log forms trending north-west and newer cheese-bob and cheese-bug spreading south-east. The cheese link may reference the creatures' grey colour or their segmented, log-like shape.

Grandparent names tie the grey colouring to elderly relatives: granny grey (the South Wales valleys — Bridgend, Rhondda, Caerphilly), granny grunter (Isle of Man), granfer grey (Somerset and Devon), daddy-granfer (around Bristol) and a scattered "grandfather". Their slow, deliberate movement may reinforce the "old person" association.

Personal names form a localised but charming category, since English dialects love assigning human names to small creatures: Billy-baker (Yeovil), curly-baker (the Somerset area), Billy-button (Weymouth) and belly button (Bournemouth) — that last a lovely example of a name drifting through mishearing over generations.

Monkey and pea names cluster mainly in Kent: monkey pea (east Kent), monkey pease (a variant spelling) and pea-bug (north and west Kent). The rare "monkey-pede" may show the influence of "millipede" or "centipede", blurring the folk boundaries between segmented creatures.

Borrowed Names from Other Creepy-Crawlies

Plenty of woodlouse names are recycled from other small arthropods — especially earwigs, centipedes and millipedes — reflecting how fluid "bug" categories are in everyday folk taxonomy. Earwig-derived names appear particularly in Scotland and northern England: eary-wig (straight from earwig), forky-tailer (a reference to earwig pincers, oddly applied to pincer-less woodlice) and the Scottish forky-goller. A few names nod to millipedes, like monkey-pede.

The spread of these borrowed names suggests many independent inventions rather than one word travelling the country, with different communities reaching similar solutions for naming the small, segmented creatures under their rocks and wood. It's a neat illustration that folk naming works by appearance, behaviour and habitat — not by the careful distinctions biologists draw between isopods, insects and myriapods.

Oddities and Rare One-Off Names

Beyond the major clusters lie genuinely puzzling one-offs. A "leather-jacket" family — including joking forms like "bomber-jacket" and "grandfather's jacket" — turns up scattered across eastern England, perhaps inspired by the tough exoskeleton. Various "-back" names appear mainly in the north-west, such as stone-back and slate-back. And the wonderfully grim "coffin cutter" shows up in isolated records with no agreed origin.

For many of these, researchers genuinely can't tell whether they're old dialect words, family in-jokes, survey mishearings or recent playful inventions. That ambiguity is part of the charm: a single household might coin a term used nowhere else on earth and keep it alive for generations before a passing researcher ever records it.

The Big Picture: Change, Loss and Standardisation

Comparing older records from the late 19th and 20th centuries with 21st-century data reveals a clear trajectory — regional diversity is collapsing toward standardisation, and relatively quickly. Woodlouse now dominates across most of the UK and Ireland, especially among younger speakers, while slater holds strong in Scotland but shows signs of retreating in parts of Northern Ireland where it once reigned unchallenged.

Many older names now survive only in pockets — Billy-baker around Yeovil, cheese-log near Reading, chucky pig in parts of Devon and Bristol, granny grey in the South Wales valleys — and increasingly belong to older speakers who aren't passing them to children. Asked where they learned their word, younger people typically cite school, television or books, all of which favour standard terms. It's a local example of broader forces: dialect levelling, media influence, education standardisation, and fewer children picking up rural vocabulary. Similar pressures apply elsewhere too — in the United States, "pill bug" and "roly poly" dominate, with regional "potato bug" — though systematic data outside the UK remains patchy.

Beyond English: Woodlouse Names in Other Languages

The pig and rolling themes aren't unique to English. Welsh offers a lovely parallel in mochyn coed, literally "wood pig" — the same porcine comparison reached independently. And many languages reference the ability of some species to roll into a ball: the North American "pill bug" (its pill shape), the widespread "roly poly" (the rolling action), and various "ball-bug" equivalents across Europe describing the same conglobation.

That rolling defence belongs specifically to the family Armadillidiidae, including Armadillidium vulgare — and the genus name itself means "little armadillo", echoing the very behaviour so many folk names describe. Not every woodlouse can do it (some flatten rather than curl), but the dramatic display has clearly captured imaginations across cultures, which may be why rolling-related names recur so often. Comprehensive global surveys remain rare, though; the British Myriapod and Isopod Group keeps records for the UK, but equivalent bodies don't exist everywhere.

Why Woodlouse Names Matter

These humble creatures are a perfect test case for studying how vocabulary varies across geography and shifts over time. Mapping terms like slater, chucky pig, cheese-log and granny grey lets researchers trace historical settlement patterns and cultural contact zones — the chucky pig distribution, for instance, closely matches known dialect boundaries in the south-west. The names preserve information about behaviour (rolling, foraging in wood), habitat (wood, stone, cellars, gardens) and perceived resemblance (pigs, peas, buttons, grey-haired relatives), complementing the biology by showing how ordinary people categorise the creatures around them.

Documenting them now preserves a slice of cultural heritage that could otherwise vanish within a generation or two. When the last person who calls woodlice "granfer greys" passes the term on to no one, that word is gone — so the survey work at places like Edinburgh keeps these words alive at least in the archive. Whether you say woodlice, slaters, chucky pigs or cheesy bobs, the next time you turn over a log and watch them scatter, it's worth a thought for which name rises to your lips — and where it came from. (If those scattering pods leave you wanting some of your own, our Armadillidium are the classic ball-rollers behind so many of these names.)

Frequently Asked Questions

How many names are there for woodlice in the UK?

Dialect surveys, including major work at the University of Edinburgh, have recorded between 250 and 300 traditional names across the British Isles, though many are local variants of the same base word. An older, often-quoted figure puts it at 176.

What's the difference between a woodlouse and a slater?

They're the same creature — just different regional names. "Woodlouse" dominates in England, Wales and the Republic of Ireland, while "slater" is the standard term in Scotland and Northern Ireland.

Why are woodlice called chucky pigs?

The pig comparison reflects their rounded bodies and rooting, foraging movement. "Chucky pig" is concentrated in south-west England (around Bristol, Bath and Devon), and the "chucky" part may echo old pig-calling cries.

Are woodlice the same as pill bugs and roly polies?

Broadly yes — these are all names for terrestrial isopods. "Pill bug" and "roly poly" specifically describe the ball-rolling species in the family Armadillidiidae, such as Armadillidium vulgare, though not every woodlouse species can roll up.