Résumé : This paper describes the structure determination of a novel diterpene, 3α‐hydroxy‐8β‐trinervita‐1,11‐diene, isolated from the defensive secretion of two West‐African termites: Trinervitermes oeconomus and T. trinervius. Copyright © 1983 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim