| S | Hasmin.Types.Dimension |
| Saturate | Hasmin.Types.FilterFunction |
| Scale | Hasmin.Types.TransformFunction |
| scale | Hasmin.Parser.TransformFunction |
| Scale3d | Hasmin.Types.TransformFunction |
| scale3d | Hasmin.Parser.TransformFunction |
| ScaleX | Hasmin.Types.TransformFunction |
| ScaleY | Hasmin.Types.TransformFunction |
| ScaleZ | Hasmin.Types.TransformFunction |
| selector | Hasmin.Parser.Selector, Hasmin.Parser.Internal |
| selectors | Hasmin.Parser.Selector |
| selectorSorting | Hasmin.Config, Hasmin |
| Separator | Hasmin.Types.Value |
| Sepia | Hasmin.Types.FilterFunction |
| shadowList | Hasmin.Parser.Value |
| ShadowText | Hasmin.Types.Value |
| ShadowV | Hasmin.Types.Value |
| ShapeRadius | Hasmin.Types.BasicShape |
| shapeRadius | Hasmin.Parser.BasicShape |
| shouldCleanRules | Hasmin.Config, Hasmin |
| shouldConvertEscaped | Hasmin.Config, Hasmin |
| shouldConvertNullPercentages | Hasmin.Config, Hasmin |
| shouldMinifyFilterFunctions | Hasmin.Config, Hasmin |
| shouldMinifyKeyframeSelectors | Hasmin.Config, Hasmin |
| shouldMinifyMicrosyntax | Hasmin.Config, Hasmin |
| shouldMinifyTimingFunctions | Hasmin.Config, Hasmin |
| shouldMinifyTransformFunction | Hasmin.Config, Hasmin |
| shouldMinifyTransformOrigin | Hasmin.Config, Hasmin |
| shouldNormalizeQuotes | Hasmin.Config, Hasmin |
| shouldRemoveDuplicateSelectors | Hasmin.Config, Hasmin |
| shouldRemoveEmptyBlocks | Hasmin.Config, Hasmin |
| shouldRemoveQuotes | Hasmin.Config, Hasmin |
| shouldUsePropertyTraits | Hasmin.Config, Hasmin |
| sideOrCorner | Hasmin.Parser.Gradient |
| simplify | Hasmin.Types.TransformFunction |
| SingleAnimation | Hasmin.Types.Value |
| SingleQuotes | Hasmin.Types.String |
| SingleTransition | Hasmin.Types.Value |
| Skew | Hasmin.Types.TransformFunction |
| skew | Hasmin.Parser.TransformFunction |
| SkewX | Hasmin.Types.TransformFunction |
| SkewY | Hasmin.Types.TransformFunction |
| Slash | Hasmin.Types.Value |
| SortingMethod | Hasmin.Config, Hasmin |
| Space | Hasmin.Types.Value |
| SRClosestSide | Hasmin.Types.BasicShape |
| SRFarthestSide | Hasmin.Types.BasicShape |
| SRLength | Hasmin.Types.BasicShape |
| SRPercentage | Hasmin.Types.BasicShape |
| Start | Hasmin.Types.TimingFunction |
| StepEnd | Hasmin.Types.TimingFunction |
| StepPosition | Hasmin.Types.TimingFunction |
| Steps | Hasmin.Types.TimingFunction |
| steps | Hasmin.Parser.TimingFunction |
| StepStart | Hasmin.Types.TimingFunction |
| stringOrUrl | Hasmin.Parser.Value |
| StringType | Hasmin.Types.String |
| stringtype | Hasmin.Parser.String, Hasmin.Parser.Value |
| StringV | Hasmin.Types.Value |
| stringvalue | Hasmin.Parser.Value |
| StyleRule | Hasmin.Types.Stylesheet |
| styleRule | Hasmin.Parser.Internal |
| stylesheet | Hasmin.Parser.Internal |
| SupportsCondInParens | Hasmin.Types.Stylesheet |
| SupportsCondition | Hasmin.Types.Stylesheet |
| supportsCondition | Hasmin.Parser.Internal |