The family has 60 to 65 genera with about 1,200 species of trees, shrubs and lianas.
The simple, oppositely arranged leaves usually have stipules and branched hairs.
There are often 2 large fleshy glands on the petiole or leaf.
Inflorescences are terminal or axillary.
Flowers are on a stalk which has 2 bracteoles anywhere on it.
The flowers are bisexual and the perianth is in 2 whorls.
There are 5 sepals whose bases are sometimes joined.
The outer surface of the sepals usually have 1 or 2, large or small fleshy glands.
There are 5 petals whose bases may be fused.
Petals have clawed bases and fringed edges.
The 10 (5) stamens in 2 (1) whorls sometimes have fused bases.
Some stamens may be infertile staminodes.
Anthers open inwards via longitudinal slits or pores.
The superior ovary has 3 (2-5) carpels that are free or fused and some may not develop.
Each has 1 style and there is one ovule per locule.
Fruits are of various types – schizocarp, samara, drupe or nut.