: pizza (plural: ZAS)
About the Word:
ZA (often styled in print as 'za) is a slang shortening of the word pizza. You may be surprised at the slang found on the tournament SCRABBLE board: BRO, HOMEY, and YO are all accepted words.
ZA is the most played word containing the letter Z (and the only playable two-letter word with the letter Z) in tournament SCRABBLE play.
Incidentally, .za is the country code for South Africa (Zuid-Afrika is Dutch for "South Africa"), but abbreviations and codes are not acceptable on the SCRABBLE board.