4 letters
- opus8
- orbs7
- ouds6
- ours5
- oust5
- outs5
- ouzo14
- ovum12
- owns8
- poms10
- pons8
- poon8
- pubs11
- puns9
- robs7
- roms7
- room7
- rubs8
- rums8
- runs6
- scum11
- shmo9
- shoo6
- shun8
- slob8
- slub9
- slum9
- smog9
- smug10
- smut8
- snib8
- snob8
- snog7
- snot5
- snow8
- snub9
- snug8
- sobs7
- solo5
- soma7
- some7
- sone5
- song7
- sons5
- sook8
- soon5
- soot4
- sorb7
- sorn5
- souk9
- soul6
- soup8
- sour5
- sous5
- sown8
- spun9
- stob7
- stub8
- stum8
- stun6
- suba8
- subs8
- sumo8
- sump11
- sums8
- sung8
- sunk10
- sunn7
- suns6
- swob10
- swum11
- sybo9
- tomb10
- toms7
- tons5
- toom7
- toon5
- tubs8
- tuns6
- udos6
- umbo11
- umps11
- unbe9
- unco9
- undo7
- unto6
- upon9
- urbs8
- urns6
- womb13
- wons8
- woos7
- yobs9
- zoom16
- zoon14
- zoos13