Is documentary a word in the Scrabble Dictionary

Yes, documentary is playable

...and is worth 22 points.

Found in the following dictionaries

Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)

"Documentary" Definition

noun

A work, such as a film or television program, presenting political, social, or historical subject matter in a factual and informative manner and often consisting of actual news films or interviews accompanied by narration.
A documentary presentation (as a film or novel).

adjective

Consisting of, concerning, or based on documents.
Presenting facts objectively without editorializing or inserting fictional matter, as in a book or film.
Being or consisting of contained or certified in writing .
Of, relating to, or employing in literature or art.