馬うま虻あぶMeanings1nounhorse botflyrare termRare zoological term for a botfly that parasitizes horses. The more common word is 馬蠅 (うまばえ).See also: 馬蠅馬うま虻あぶはウマバエ科かの昆こん虫ちゅうで、馬うまに寄き生せいする。The horse botfly is an insect of the family Gasterophilidae that parasitizes horses.