Trees, shrubs, climbers, or herbs; stems mostly 4-angled; leaves opposite; or whorled, simple or compound: inflorescences racemes, spikes, heads, corymbs, or cymes; calyx tubular, 4-8-lobed; stamens 8-4, or 2, unequal; anthers versatile, 2-celled; small staminodia rarely present; disc none; ovary 2-8-celled; cells 1-2- ovulate; style simple or bifid; fruit a drupe, capsule or schizocarp; seeds 1-8, endosperm none. Many spp. somewhat to very fragrant-pungent (foliage, etc.) owing to essential oils. 76 genera and about 3000 species, tropical and in the temperate zone of the Southern Hemisphere.