flying squirrel
/ˌflaɪɪŋ ˈskwɪrəl/
/ˌflaɪɪŋ ˈskwɜːrəl/
Etymology
GreekLatinOld FrenchEnglish
The animal's name joins 'flying', from its gliding leaps between trees, with 'squirrel'. 'Squirrel' goes back to a Greek word meaning 'shadow-tail', describing how the bushy tail can shade the body, and it reached English through Latin and Old French. The creature does not truly fly, so 'flying' here describes its long, gliding jumps rather than wing-powered flight.
First known use
1591
1591, in the meaning defined above