Yes, frost is a Scrabble word!

Verb

1. Decorate with frosting

2. Provide with a rough or speckled surface or appearance

3. Cover with frost

4. Damage by frost

Noun

1. Ice crystals forming a white deposit (especially on objects outside)

2. Weather cold enough to cause freezing

3. The formation of frost or ice on a surface

4. United States poet famous for his lyrical poems on country life in New England (1874-1963)