Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† gargărīzo (also gargaridio, Varr. ap. Non. 117, 7; v. the letters D and Z: gargarisso, Varr. L. L. 6, § 96 Müll.; M. Aurel. ap. Front. Ep. ad M. Caes. 4, 6 Mai.), āvi, ātum, 1, v. n. and a., = γαργαρίζω, to gargle, take a gargle, use as a gargle.