Yes, masses is a Scrabble word!

Verb

1. Join together into a mass or collect or form a mass

Noun

1. The common people generally

2. The property of a body that causes it to have weight in a gravitational field

3. (often followed by `of') a large number or amount or extent

4. An ill-structured collection of similar things (objects or people)

5. (Roman Catholic Church and Protestant Churches) the celebration of the Eucharist

6. A body of matter without definite shape

7. The common people generally

8. The property of something that is great in magnitude

9. A musical setting for a Mass

10. A sequence of prayers constituting the Christian Eucharistic rite

11. A shot in billiards made by hitting the cue ball with the cue held nearly vertically; the cue ball spins around another ball before hitting the object ball