Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
pillĕo, āvi, ātum, 1, v. a. [id], to place the pilleus on a person’s head, to bonnet him, in token of manumission: pilleari et rudem accipere possunt, Mos. et Rom. Leg. Coll. 11, 7, 4.