Yes, go is playable
...and is worth 4 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Go" Definition
Word Fact:
"Go!" is the shortest grammatically correct sentence in English.
noun
A Japanese game for two, played with counters on a board that is ruled with 19 vertical and 19 horizontal lines.
An attempt; an effort: had a go at acting.
Informal Energy; vitality: had lots of go.
Informal Informal A situation in which planned operations can be effectuated: The space mission is a go.
phrasal-verb
Go about To set about to do; undertake: Go about your chores in a responsible way.
Go along To cooperate: They get along by going along.
Go around To go here and there; move from place to place.
Go around To have currency: rumors going around.
Go around To satisfy a demand or requirement: just enough food to go around.
adjective
Informal Functioning correctly and ready for action: All systems are go.
Functioning properly being in good and ready condition .
verb-intransitive
Informal To begin an act: Here goes!.
Informal To excrete waste from the bladder or bowels.
Informal Used as an intensifier when joined by and to a coordinate verb: She went and complained to Personnel.
To be a contributing factor: It all goes to show us that the project can be completed on time.
verb-transitive
Informal To bet: go $20 on the black horse.
Informal To enjoy: I could go a cold beer right now.
Informal To participate to (a given extent): Will you go halves with me if we win the lottery?.
Informal To take on the responsibility or obligation for: go bail for a client.
Sports To have as a record: went 3 for 4 against their best pitcher.
We love the game of Scrabble®, which is why we created Free Scrabble Dictionary - a simple lookup tool to check if the word you want to play is valid in the game of Scrabble®. At the top of every page, you can enter your word and click "Search Dictionary." We'll let you know whether your word is playable and provide a few definitions as well.