Yes, mass is a Scrabble word!
...and is worth 6 points in Scrabble, and 7 points in Words with Friends
mass
Verb
1. Join together into a mass or collect or form a mass
Adjective
1. Formed of separate units gathered into a mass or whole
Noun
1. The property of a body that causes it to have weight in a gravitational field
2. (often followed by `of') a large number or amount or extent
3. An ill-structured collection of similar things (objects or people)
4. (Roman Catholic Church and Protestant Churches) the celebration of the Eucharist
5. A body of matter without definite shape
6. The common people generally
7. The property of something that is great in magnitude
8. A musical setting for a Mass
9. A sequence of prayers constituting the Christian Eucharistic rite
What Scrabble words can I make with the letters in mass?
3 Letter Words
2 Letter Words