| Term | Definition |
| smug | self-satisfied |
| snare | to trap |
| sneer | to look at with contempt; to scorn; to deride |
| snicker | to laugh in a half-suppressed way |
| snippet | a small fragment |
| snivel | to whine; to complain |
| sober | not drunk; serious |
| sobriquet | nickname; assumed name |
| sodden | soaked; damp |
| sojourn | a brief stay or visit |
| solace | comfort |
| solar | pertaining to the sun |
| solecism | ungrammatical usage; an error or inconsistency |
| solicit | to ask; to seek; to try to get an order in business |
| solicitude | concern anxiety |
| solilquy | act of talking to oneself |
| solipsistic | pertaining to the theory that only one self exists or can be proved to exist |
| solitude | loneliness |
| solon | a wise man |
| solvent | having the ability to pay a debt; a substance that dissolves another |