Tropical
来自Big Physics
late Middle English (denoting the point on the ecliptic reached by the sun at the solstice): via Latin from Greek tropikos, from tropē ‘turning’, from trepein ‘to turn’.
wiktionary
tropic + -al
etymonline
tropical (adj.)
1520s, "pertaining to the celestial tropics," from tropic + -al (1). In reference to the torrid zones of the earth, from 1690s. Meaning "hot and lush like the climate of the tropics" is first attested 1834.