acid (adj.) Copy link • acid (adj.); ăcĭdus (ăcerbus is sour, i. e. unripe): a. sorb apples, a. sorba, Virg.: a. elecampane, a. inula, Hor. Somewhat acid or a little acid, ăcĭdulus, Plin.: sŭbăcĭdus, Col. To become a., ăcesco, cŏăcesco, ăcŭi, 3: all wines do not become a. with age, non omne vinum vetustate c., Cic.: Cels.: v. sour.