Entry 1 sense Webster, 1913 Forsythia /fôr-sĭth'-ē-ə/ · For·syth·i·a · IPA /[fɔɹˈsɪθijə]/ 01 a. A shrub of the Olive family, with yellow blossoms. 1. A shrub of the Olive family, with yellow blossoms.(Bot.)