1Any of numerous cultivated varieties of the fig tree (Ficus carica) having blue or purple fruits (more fully blue fig tree).
2Australian the large tree Elaeocarpus grandis (also called E. angustifolius) (family Elaeocarpaceae) of eastern Australia, which has small blue fruits.
Origin
Early 17th century; earliest use found in Ben Jonson (?1573–1637), poet and playwright.