Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
virgĭdēmĭa, ae, f. [formed from virga, after the analogy of vindemia], a harvest of rods, i. e. of stripes or blows, Plaut. Rud. 3, 2, 22; Varr. ap. Non. p. 187, 13.