[fawr-tis] 
adjective, noun, plural -tes [-teez] . Phonetics| 1. | pronounced with considerable muscular tension and breath pressure, resulting in a strong fricative or explosive sound. In stressed position (p, t, k, ch, f, th, s, sh) and sometimes (h) are fortis in English as compared with (b, d, g, j, v, th̸, z, and zh), which are lenis. Compare lenis. |
| 2. | a fortis consonant. |
| for·tis (fôr'tĭs) adj. Articulated with relatively strong pressure of the airstream below the glottis, as in English (p) and (t) compared with (b) and (d). n. A fortis consonant. [Latin, strong; see fort.] |