Why was "tantrum" trending last week?
Old English mygg, mycg "gnat," from Proto-Germanic *mugjon (cf. Swedish mygga, Old Saxon muggia, Middle Dutch mugghe, Dutch mug, Old High German mucka, German Mücke "midge, gnat"). No certain cognates beyond Germanic, unless doubtful Armenian mun "gnat" and Albanian mize "gnat" are counted. But Watkins, Klein and others suggest an imitative root used for various humming insects and a relationship to Latin musca (see mosquito). Meaning "diminutive person" is from 1796.
Any of various gnatlike flies, some species of which, such as the biting midges of the family Ceratopogonidae, serve as vectors for parasitic diseases.