Yes, dot is a Scrabble word!
...and is worth 4 points in Scrabble, and 4 points in Words with Friends
dot
Verb
1. Scatter or intersperse like dots or studs
2. Distribute loosely
3. Make a dot or dots
4. Mark with a dot
Noun
1. A very small circular shape
2. The United States federal department that institutes and coordinates national transportation programs; created in 1966
3. The shorter of the two telegraphic signals used in Morse code
4. Street name for lysergic acid diethylamide
What Scrabble words can I make with the letters in dot?
3 Letter Words
2 Letter Words