Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
aequănĭmus, a, um [aequus-animus], adj., even-tempered, patient, composed, calm: aequanimus fiam, Aus. Sept. Sap. 3: nulla fuit res parva umquam aequanimis, id. Idyll. 3, 9