Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
per-sĭmĭlis, e, adj., very like or similar (class.), Cic. Part. Or. 7, 26: statuam istius persimilem deturbant, id. Pis. 38, 93: isti tabulae fore librum Persimilem, cujus, etc., Hor A. P 6 sq.