Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
gargărīzātĭo, ōnis, f. [gargarizo], a gargling, Cels. 5, 22 fin.; Plin. 22, 25, 57, § 120; 23, 8, 80, § 157: lactis, id. 30, 4, 11, § 31.