The specific epithet trichotoma is from the Greek meaning 'three parts', referring to the three-branched inflorescence.

[2] Mastixia trichotoma grows as a tree measuring up to 40 metres (130 ft) tall with a trunk diameter of up to 50 centimetres (20 in).

The smooth to fissured bark is yellowish grey to grey-brown.

[2] Mastixia trichotoma grows naturally in the Andaman and Nicobar Islands, Thailand, Sumatra, Peninsular Malaysia, Java, Borneo, Sulawesi, the Moluccas and Mindanao.

[2][1] Its habitat is mixed dipterocarp forests from sea-level to 1,800 metres (6,000 ft) elevation.