pecuniary UK /pɪˈkjuːn(jə)ɹi/US /pəˈkjuniˌɛɹi/ adjective1 •Of, or relating to, money; monetary, financial.Perhaps the reader will suppose after this that the doctor had some pecuniary interest of his own in arranging the squire's loans; or, at any rate, he will think that the squire must have thought so. — 1858