hairstreak n 1: small butterflies having striped markings under the wings [syn: {hairstreak}, {hairstreak butterfly}]
Hairstreak \Hair"streak`\ (-str[=e]k`), n. A butterfly of the genus {Thecla}; as, the green hairstreak ({Thecla rubi}). [1913 Webster]
Thecla \Thec"la\, n. Any one of many species of small delicately colored butterflies belonging to {Thecla} and allied genera; -- called also {hairstreak}, and {elfin}. [1913 Webster]