1. (a.) Past the middle of a lifetime; pertaining to the fall season; as, autumnal fruits; autumnal plants\.

2. (a.) Past the middle of life; in the third stage.

arctic autumn autumnal beryl-green berylline blood-hot blood-warm blue-green bluish-green boreal brumal calid canicular chartreuse chloranemic chlorine chlorotic citrine citrinous emerald equatorial equinoctial foliaged genial glaucescent glaucous glaucous-green grassy green green as grass green-blue greenish greenish-blue greenish-yellow greensick hibernal hiemal holly ivy ivy-green leafy leaved luke lukewarm midsummer midwinter mild olivaceous olive olive-green out of season porraceous room-temperature seasonal smaragdine solstitial spring springlike subtropical summer summerlike summerly summery sunny sunshiny temperate tepid thermal thermic toasty tropical unfrozen verdant verdurous vernal vernant vert virescent warm warm as toast warmish winter winterlike wintery wintry yellowish-green