Why are they called lice? - briefly
The name originates from Old English “lǣs,” meaning a parasite, which later merged with Latin “pediculus” (little foot) to form the modern term. The word reflects the insect’s habit of clinging to hosts with its small claws.
Why are they called lice? - in detail
The term “lice” derives from Old English lūs, a word that denoted any small, wingless parasite that feeds on the blood or skin of mammals and birds. This Old English form traces back to Proto‑Germanic lusaz, which is also the source of German Laus and Dutch luis. The Proto‑Germanic root is linked to the Proto‑Indo‑European root *leu‑, meaning “to wash” or “to rinse,” a possible reference to the parasite’s habit of moving through the host’s hair or feathers, reminiscent of a cleansing motion.
In classical antiquity, the Greek word πύληξ (pýlēx) identified the same creature. Latin adopted the Greek term as pulex, which appears in scientific nomenclature (e.g., Pediculus humanus). The transition from pulex to the English “lice” occurred through the influence of Germanic languages, not through direct borrowing from Latin.
The modern plural form “lice” reflects an irregular pluralization pattern common in Old English, where singular nouns ending in a vowel often formed plurals by adding -e or -en and later simplifying to -ice. This pattern survived in the word for the insect, while the singular “louse” retained the older form.
Key points summarizing the etymology:
- Old English lūs → Proto‑Germanic lusaz → Germanic cognates (German Laus, Dutch luis).
- Greek πύληξ → Latin pulex → scientific usage (e.g., Pediculus).
- Irregular plural “lice” originates from Old English pluralization rules, distinct from the singular “louse.”
Thus, the name reflects a linguistic lineage that spans Germanic, Greek, and Latin traditions, with the irregular plural persisting as a historical artifact of early English grammar.