| sensible to |
| shark(sharp, smart, intelligent, clever, astute) |
| shifty(smooth, sharp, cunning, deceitful, sly) |
| skeptical(adjective, cool, refined, practical, mature) |
| skillful(smart, shrewd, clever) |
| slippery(smooth, sharp, intelligent, clever, subtle) |
| stagy(adjective, cool, refined, practical, mature) |
| studied(adjective, cool, refined, practical, mature) |
| suave(adjective, cool, refined, practical, mature) |
| subtle(smooth, sharp, smart, deceitful, clever) |
| svelte(adjective, cool, refined, practical, mature) |
| switched on(expression, refined, practical, mature, cultured) |
| undeceived |
| underhand(sharp, smart, intelligent, clever, astute) |
| up-to-date |
| up on(expression, sharp, smart, intelligent, clever) |
| uptown(adjective, cool, refined, practical, mature) |
| urbane(adjective, smooth, refined, practical, mature) |
| versed(adjective, knowing) |
| wary(smooth, sharp, smart, shrewd, clever) |