Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
tītillātĭo, ōnis, f. [titillo], a tickling, titillation: voluptates, quibus quasi titillatic sensibus adhibetur, Cic. N. D. 1, 40, 113: non est voluptatum tanta quasi titillatio in senibus, id. Sen. 14, 47; Hier. Ep. 52, 3: corporis, Sen. Ep. 92, 6.