Crab-louse

noun
1.
See under (def 1).
[noun lous; verb lous, louz] /noun laʊs; verb laʊs, laʊz/
noun, plural lice
[lahys] /laɪs/ (Show IPA), for 1–3, louses for 4.
1.
any small, wingless insect of the order Anoplura (sucking louse) parasitic on humans and other mammals and having mouthparts adapted for sucking, as Pediculus humanus (body louse or head louse) and Phthirius pubis (crab louse or pubic louse)
2.
any insect of the order Mallophaga (bird louse, biting louse, or chewing louse) parasitic on birds and mammals, having mouthparts adapted for biting.
3.
.
4.
Slang. a contemptible person, especially an unethical one.
verb (used with object), loused, lousing.
5.
to .
Verb phrases
6.
louse up, Slang. to spoil; botch:
Miscasting loused up the movie.
noun
1.
a parasitic louse, Pthirus (or Phthirus) pubis, that infests the pubic region in man
/laʊs/
noun (pl) lice (laɪs)
1.
any wingless bloodsucking insect of the order Anoplura: includes Pediculus capitis (head louse), Pediculus corporis (body louse), and the crab louse, all of which infest man related adjective pedicular
2.
biting louse, bird louse, any wingless insect of the order Mallophaga, such as the chicken louse: external parasites of birds and mammals with biting mouthparts
3.
any of various similar but unrelated insects, such as the plant louse and book louse
4.
(slang) (pl) louses. an unpleasant or mean person
verb (transitive)
5.
to remove lice from
6.
(foll by up) (slang) to ruin or spoil
n.

“parasitic insect infecting human hair and skin,” Old English lus, from Proto-Germanic *lus (cf. Old Norse lus, Middle Dutch luus, Dutch luis, Old High German lus, German Laus), from PIE *lus- “louse” (cf. Welsh lleuen “louse”). Slang meaning “obnoxious person” is from 1630s. The plural lice (Old English lys) shows effects of i-mutation. The verb meaning “to clear of lice” is from late 14c.; to louse up “ruin, botch” first attested 1934, from the literal sense (of bedding), from 1931.

louse (lous)
n. pl. lice (līs)
Any of numerous small, flat-bodied, wingless biting or sucking insects of the orders Mallophaga or Anoplura, many of which are external parasites on humans.

crab louse n.
A sucking louse that generally infests the pubic region and causes severe itching.

noun

An obnoxious and despicable person, esp one who is devious and undependable; bastard, crumb: We kicked the dirty louse out when he said that (1633+)