Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
rĕ-parco (-perco), ĕre, v. n., to be sparing with any thing; to spare, to refrain or abstain from (ante- and post-class.): utinam a principio rei pepercisses meae, Ut nunc repercis saviis, Plaut. Truc. 2, 4, 25 (where Speng. conjectures repercisses): ex nullā facere id si parte reparcent, if they in no way refrain from doing (i. e. believing) this, Lucr. 1, 667 Munro: istius muneris operam non reparcam, Symm. Ep. 1, 33.