A lilac or a lilac tree is a small tree which has sweet-smelling purple, pink, or white flowers in large, cone-shaped groups.
Lilacs grew against the side wall.
...a twig of lilac.
Lilacs are the flowers which grow on this tree.
...a vase of tulips, lilies, lilacs and primroses.
Her hair smelt of lilac.
2. colour
Something that is lilac is pale pinkish-purple in colour.
All shades of mauve, lilac, lavender and purple were fashionable.
lilac in British English
(ˈlaɪlək)
noun
1. Also called: syringa
any of various Eurasian oleaceous shrubs or small trees of the genus Syringa, esp S. vulgaris (common lilac) which has large sprays of purple or white fragrant flowers
2. French lilac
3.
a.
a light or moderate purple colour, sometimes with a bluish or reddish tinge
b.
(as adjective)
a lilac carpet
Word origin
C17: via French from Spanish, from Arabic līlak, changed from Persian nīlak bluish, from nīl blue
lilac in American English
(ˈlaɪlək; ˈlaɪˌlɑk; ˈlaɪˌlæk)
noun
1.
any of a genus (Syringa) of hardy shrubs or trees of the olive family, with large clusters of tiny, fragrant flowers ranging in color from white, through many shades of lavender, to deep crimson
2.
the flower of this plant
3.
pale purple
adjective
4.
of a pale-purple color
Word origin
Fr (now lilas) < Ar līlak < Pers līlak, nīlak, bluish < nīl, indigo < Sans nila, dark blue, indigo