evertorAnat.|ɪˈvɜːrtə(r)| [f. evert v. + -or.] Any muscle which turns or rotates a part outward. 1903Lancet 4 July 56/2 Either the evertor or invertor is out of use.1967Gray's Anat. (ed. 34) 717 When the foot is off the ground, it [sc. the peroneus longus] is an evertor.