4 letters:
basa, bava, casa, cava, dasa, gaza

5 letters:
baffa, basha, bassa, boffa, botha, bozza, casca, cas a, catha, das a, gas a, gatha, gaz a, gotha, kasha, kassa, kasza, katha, pasha, pas a, paz a, tassa, tazza

6 letters:
bash a, bass a, bath a, bhatia, boss a, calf a, casa a, cashaw, cash a, cass a, dash a, gaff a, gass a, gaza a, kasbah, pascha, pass a, path a, toth a

7 letters:
cache a, cause a, cough a, ghosh a