Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
bŏiae, ārum, f. [bos], a collar for the neck, κλοιός (orig. of leather; hence the name; but later of wood or iron), Fest. p. 29; Isid. Orig. 5, 27, 12: boia κλοιός, Gloss. Vet.: pedicae boiae, Plaut. As. 3, 2, 5: attrita boiis colla, Prud. Psych. praef. 34.
For boiam terere, v. Boii fin.