[n] the next to last syllable in a word
[adj] next to the last; "the author inadvertently reveals the murderer in the penultimate chapter"; "the figures in the next-to-last column"
\Pe*nul"ti*mate\, a. Last but one; as, the penultimate syllable, the last syllable but one of a word.
\Pe*nul"ti*mate\, n. The penult.