noun, plural lice [lahys]
for 1–3, lous⋅es for 4, verb, loused, lous⋅ing.| 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. | plant louse. |
| 4. | Slang. a contemptible person, esp. an unethical one. |
| 5. | to delouse. |
| 6. | louse up, Slang. to spoil; botch: Miscasting loused up the movie. |

| bird louse n. See biting louse. |
| biting louse n. Any of several small, wingless, biting insects of the order Mallophaga that are external parasites on birds. Also called bird louse. |
louse
[lɑʊs]
|
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.
bird louse
any of two groups of chewing lice (order Phthiraptera) that live on birds and feed on feathers, skin, and sometimes blood. Probably all bird species have these chewing lice. Although they are not harmful, if they become too numerous, their irritation may cause the bird to damage itself by scratching and may even interfere with egg production and the fattening of poultry.
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