upper carboniferous period

English Thesaurus

1. from 310 million to 280 million years ago; warm climate; swampy land (noun.time)

instance hypernym	:	geological period, period,
definition	:	a unit of geological time during which a system of rocks formed (noun.time)

part meronym	:	carboniferous, carboniferous period,
definition	:	from 345 million to 280 million years ago (noun.time)