I. ˌsü-pər-ˈkül
Date: 1906
transitive verb
: to cool below the freezing point without solidification or crystallization
intransitive verb
: to become supercooled
II. adjective
Date: 1970
: extremely cool: as
a. : showing extraordinary reserve and self-control
b. : being the latest style or fashion
supercool sunglasses