3 Letter Words:
* alt
* mat
* sat
* slam
* stal
* tam
4 Letter Words:
* last
* malt
* mast
* salt
* slat
* slam
* stal
* tala
5 Letter Words:
* atlas
* lasts
* malts
* maste (archaic, meaning "to chew")
* salts
* slats
* small
Let me know if you'd like me to try and find any more obscure or uncommon words!