Yes, tuck is a Scrabble word!
...and is worth 10 points in Scrabble, and 12 points in Words with Friends
tuck
Verb
1. Fit snugly into
2. Make a tuck or several folds in
3. Draw together into folds or puckers
Noun
1. Eatables (especially sweets)
2. (sports) a bodily position adopted in some sports (such as diving or skiing) in which the knees are bent and the thighs are drawn close to the chest
3. A narrow flattened pleat or fold that is stitched in place
4. A straight sword with a narrow blade and two edges
What Scrabble words can I make with the letters in tuck?
3 Letter Words
2 Letter Words