The word quadriphonics uses 13 letters:acdhiinopqrsu.

QUADRIPHONICS is playable in:

Words With Friends33
Scrabble US30
Scrabble UK30

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

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