louse has definitions from the field of zoology
1
[ noun ] (zoology) wingless usually flattened blood-sucking insect parasitic on warm-blooded animals

Synonyms

sucking_louse

Used in print

(Robert Penn Warren, Wilderness....)

He thought_of Simms_Purdew snoring on his bunk while Pullen_James crouched by the hearth , skirmishing an undershirt for lice , and a wet log sizzled .

2
[ noun ] has a nasty or unethical character undeserving of respect

Synonyms

worm dirt_ball insect

Related terms

unpleasant_person

3
[ noun ] (zoology) any of several small insects especially aphids that feed by sucking the juices from plants

Synonyms

plant_louse

4
[ noun ] (zoology) wingless insect with mouth parts adapted for biting; mostly parasitic on birds
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