Lewis & Short

aequănĭmis [aequus-animus], adj. in Vet. Onomast. = εὐγνῶμων, kind, mild.
Adv.:
aequănĭmĭter, calmly, with equanimity (only in later Lat.), Macr. S. 2, 4; Sulp. Dial. 1, 14; Amm. 19, 10; Tert. Patient. 8 al.