ex·pres·sio uni·us est ex·clu·sio al·ter·i·us /ik-'spre-shē-ō-yu̇-'nī-əs-ˌest-ik-'sklü-zē-ō-ȯl-'tir-ē-əs, ek-'spre-sē-ō-ü-'nē-u̇s-ˌest-ek-'sklü-sē-ō-äl-te-'rē-u̇s/ n [New Latin, the explicit mention of one (thing) is the exclusion of another]: a principle in statutory construction: when one or more things of a class are expressly mentioned others of the same class are excluded
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.