Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† lexis, ĕos (acc. plur. -eis), f., = λέξις, a word (ante-class. and post-Aug.): quam lepide lexeis compostae! Lucil. ap. Cic. de Or. 3, 43, 171; Charis. 249; 251 P.