mite
n. countablen. a tiny creature that looks like a spider and lives in dust, on plants, or on animals. It can also mean a very small amount of something or a small child you feel sorry for.
n. any of numerous small acari that are often parasitic on animals or plants, or live in decaying matter. In a figurative sense, refers to a very small object, creature, or amount.
Dust mites are too small to see without a microscope.
The poor little mite had been wandering the streets alone for hours before someone found him.
While the individual mite is nearly invisible to the naked eye, a significant infestation can cause noticeable damage to crops or trigger severe allergic reactions in humans.
From Middle English mite, from Old English mīte (“mite, tiny insect”), from Proto-West Germanic mītā, from Proto-Germanic mītǭ (“biting insect”, literally “cutter”), from maitaną (“to cut”), from Proto-Indo-European mey- (“small”) or *meh₂y- (“to cut”). Akin to Old High German mīza (“mite”), Middle Dutch mīte (“moth, mite”), Dutch mijt (“moth, mite”), Danish mide (“mite”).
Often used with 'little' when referring to a child or animal to express sympathy.