Psi or Y, e.g

• The next to last syllable in a word
• Syllable before the last
• Word's next-to-last syllable
• Next to the last syllable of a word
• Next-to-last syllable

Wiktionary Word definitions in Wiktionary
n. 1 The next-to-last syllable of a word. 2 The next to the last in a series.

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Penult \Pe"nult\, n. [Abbreviated fr. penultima.] (Gram. & Pros.) The last syllable but one of a word; the syllable preceding the final one.

WordNet Word definitions in WordNet
n. the next to last syllable in a word [syn: penultima , penultimate ]

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
"last but one," 1530s, abbreviation of penultima . As a noun from 1570s.