| soda jerk | | | |
| sod off | | | |
| so far | | | |
| so far so good | | | |
| soft | | | |
| soften someone's cough | | | |
| soften the blow | | | |
| soften the ground | | | |
| soften up | | | |
| soft kill | | | |
| soft Mick | | | |
| soft sawder | | | |
| soft shoe | | | |
| soft-soap | | | |
| soft spot | | | |
| soft touch | | | |
| soft underbelly | | | |
| so long as | | | |
| some old | | | |
| someone's cup of tea | | | |
| someone's goose is cooked | | | |
| someone's heart is in | | | |
| someone's jaw dropped | | | |
| some people | | | |
| some pumpkins | | | |
| something awful | | | |
| something is rotten in the state of Denmark | | | |
| something like | | | |
| sometimes a cigar is just a cigar | | | |
| somewhere along the line | | | |
| somewhere over the rainbow | | | |
| so much for | | | |
| song and dance | | | |
| songbird | | | |
| son of Adam | | | |
| son of the morning | | | |
| sore point | | | |
| sore-thumbish | | | |
| sort oneself out | | | |
| sort out | | | |
| so there | | | |
| so true, bestie | | | |
| sound asleep | | | |
| sounds like a plan | | | |
| soup sandwich | | | |
| soup-to-nuts | | | |
| sour grapes | | | |
| sour note | | | |
| sour stomach | | | |
| sour tooth | | | |
| sow dragon's teeth | | | |
| sow one's wild oats | | | |
| sow the seeds of | | | |
| space out | | | |
| spanielize | | | |
| spanielship | | | |
| spank the monkey | | | |
| spanner in the works | | | |
| spare no effort | | | |
| spare someone's blushes | | | |
| spare someone the details | | | |
| spare tire | | | |
| spare tyre | | | |
| spark spread | | | |
| speak for | | | |
| speak for oneself | | | |
| speak in circles | | | |
| speak of the devil | | | |
| speak of the devil and he appears | | | |
| speak of the devil and he shall appear | | | |
| speak one's mind | | | |
| speak out | | | |
| speak someone's language | | | |
| speak to | | | |
| speak up | | | |
| speak with a forked tongue | | | |
| spear carrier | | | |
| spearhead | | | |
| special delivery | | | |
| special military operation | | | |
| special needs | | | |
| special relationship | | | |
| special treatment | | | |
| specialty crop | | | |
| spectator sport | | | |
| speech is silver, silence is golden | | | |
| speed merchant | | | |
| speed up | | | |
| Speedy Gonzales | | | |
| sperm donor | | | |
| spick-and-span | | | |
| spicy | | | |
| spicy tooth | | | |
| spiff up | | | |
| spill ink | | | |
| spill juice | | | |
| spill one's guts | | | |
| spill one's seed | | | |
| spill the beans | | | |
| spilt milk | | | |