[TA]Avoid pronouncing this word sin'ister like its English derivative. This form of the adjective is used only with masculine nouns (ventriculus sinister, plural ventriculi sinistri). With feminine nouns the form sinistra is used (auricula sinistra, plural auriculae sinistrae), and with neuter nouns the form sinistrum (atrium sinistrum, plural atria sinistra). Left. [L.]