Etymograph

English

threadworm

From thread + worm.

A compound of thread + worm

Proto-Indo-European *terh₁- ‘rub’

Proto-Indo-European *treh₁-tu-s

Proto-Germanic *þrēduz ‘thread’

Old English þrǣd

Middle English thred

English thread

Proto-Indo-European *wr̥mis

Proto-Germanic *wurmiz

Proto-West Germanic *wurmi

Old English weorm

Middle English werm

English worm

Today it means

noun A parasitic roundworm, Strongyloides stercoralis, which causes strongyloidiasis.

Sources

Sources: Wiktionary, “threadworm”. By Wiktionary contributors, CC BY-SA 4.0, via kaikki.org (dump of Oct 3 2026); text adapted and restructured. Language periods are conventional ranges, not dates for this word. License.

Etymograph / threadworm