Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
cŏëmptiōnālis (in MSS. also contracted cōmptiōnālis; cf. Lachm. ad Lucr. p. 135), e, adj. [coëmptio], pertaining to a sham sale or a sham marriage: senex, who was made use of in such a performance (cf. Cic. Mur. 12, 27); accordingly, poor, worthless, Plaut. Bacch. 4, 9, 52.
Of a low kind of slaves, Cur. ap. Cic. Fam. 7, 29, 1.