hairstreak

noun hair·streak \ ˈher-ˌstrēk \

Definition of hairstreak

: any of a subfamily (Theclinae of the family Lycaenidae) of small butterflies usually having striped markings on the underside of the wings and thin filamentous projections from the hind wings

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Recent Examples of hairstreak from the Web

Last summer, the elusive white-letter hairstreak butterfly was spotted in Scotland for the first time in 133 years.

— brigit katz, Smithsonian, "This Butterfly Recently Returned to Scotland. Now, It’s Laying Eggs," 19 Feb. 2018
The Butterfly Conservation team has observed the white-letter hairstreak gradually spreading northwards, possibly due to warming climates.

— brigit katz, Smithsonian, "This Butterfly Recently Returned to Scotland. Now, It’s Laying Eggs," 19 Feb. 2018
The white-letter hairstreak, which is native to the UK, has come under severe threat in recent years.

— brigit katz, Smithsonian, "Elusive Butterfly Spotted in Scotland For the First Time in 133 Years," 17 Aug. 2017
In 1884, a white-letter hairstreak butterfly was spotted flitting about in Scotland.

— brigit katz, Smithsonian, "Elusive Butterfly Spotted in Scotland For the First Time in 133 Years," 17 Aug. 2017
The Fulvous hairstreak, another brown butterfly that feeds on Brazilian pepper, is now showing up north of Melbourne.

— jenny staletovich, miamiherald, "What counting Florida butterflies can tell the world about climate change," 7 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hairstreak.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.