The word quinquennially uses 14 letters:aeiillnnnqquuy.

QUINQUENNIALLY is playable in:

Words With Friends41
Scrabble US35
Scrabble UK35

quinquennially is a valid word in this word list. For a definition, see the external dictionary links below.

Try a search for quinquennially in these online resources (some words may not be found):
Wiktionary - OneLook Dictionaries - Merriam-Webster - Google Search
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