a diphthong in which the first of two apparent vocalic elements is of lesser stress or sonority than the second, as the (wä) in guava [gwah-vuh] /ˈgwɑ və/.
Compare falling diphthong.
Origin of rising diphthong
First recorded in 1885–90
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019