Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
1. anfractus (not amfr-), a, um, P. a. [qs. from anfringo], winding, bending, cooked: spatia, Amm. 29, 5.
Hence, subst.: anfractum, i, n., a winding, a crook, curve (ante-class. for the class. anfractus, us): terrarum anfracta, Att. ap. Varr. L. L. 7, § 15 Müll. (Trag. Rel. p. 151 Rib.): in anfracto, Varr. ib.: cavata aurium anfracta, Varr. ap. Non. p. 193, 5.