Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† amphĭtăpa, ae, f., = ἀμφιτάπης, a coverlet, shaggy on both sides: dormire super amphitapa bene molli, Varr. ap. Non. 540, 30; Lucil. ib.; Dig. 34, 2, 24.