Superdense is valid Scrabble Word

Is superdense a scrabble word?
Official Scrabble Players Dictionary NO
Official Tournament and Club Word List NO
Collins Scrabble Words YES
Is superdense valid Words with Friends?
Words with Friends NO

Definitions for SUPERDENSE in dictionary:

Find what other words can be done using letters: "superdense"
https://scrabble-word.com/finder/superdense
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