Previous studies have suggested that previews of words prior to fixation can be processed orthographically, but not semantically, during reading of sentences (K. Rayner, D. A. Balota, & A. Pollatsek, 1986). The present study tested whether semantic processing of previews can occur within words. The preview of the second constituent of 2-constituent Finnish compound nouns was manipulated. The previews were either identical to the 2nd constituent or they were incorrect in the form of a semantically related word, a semantically unrelated word, or a semantically meaningless nonword. The results indicate that previews of 2nd constituents within compound words can be semantically processed. The results have important implications for understanding the nature of preview and compound word processing. These issues are crucial to developing comprehensive models of eye-movement control and word recognition during reading. (Contains 4 tables and 7 footnotes.)