| SameQ | Howl.Expr.Syntax, Howl.Expr |
| SeqEq | Howl.Eval |
| SeqType | Howl.Pat |
| seqType | Howl.Pat |
| Sequence | Howl.Expr.Syntax, Howl.Expr |
| sequentialRules | Howl.Eval.Context |
| Set | Howl.Expr.Syntax, Howl.Expr |
| setAttributes | Howl.Eval.Context |
| setDef | Howl.Builtins.Context |
| SetDelayed | Howl.Expr.Syntax, Howl.Expr |
| setDelayedDef | Howl.Builtins.Context |
| setErrorLineHandler | Howl.Eval.Context |
| setFlat | Howl.Eval.Context |
| setHoldType | Howl.Eval.Context |
| setNumericFunction | Howl.Eval.Context |
| setOrderless | Howl.Eval.Context |
| setOutputLineHandler | Howl.Eval.Context |
| SingleEq | Howl.Eval |
| singletonSubstitutionSet | Howl.Eval |
| Slot | Howl.Expr.Syntax, Howl.Expr |
| SlotSequence | Howl.Expr.Syntax, Howl.Expr |
| Solo | Howl.Util |
| solveMatchMaybe | Howl.Eval |
| splits1K | Howl.Util |
| splitsK | Howl.Util |
| subSequencesK | Howl.Util |
| Substitution | Howl.Eval |
| SubstitutionSet | Howl.Eval |
| Subtract | Howl.Expr.Syntax, Howl.Expr |
| Symbol | |
| 1 (Type/Class) | Howl.Symbol.Symbolize, Howl.Symbol, Howl |
| 2 (Type/Class) | Howl.Symbol.Simple |
| symbol | Howl.Pat |
| symbolFromShortText | |
| 1 (Function) | Howl.Symbol.Simple |
| 2 (Function) | Howl.Symbol.Symbolize, Howl.Symbol |
| SymbolRecord | Howl.Eval.Context |
| symbolRecordTable | Howl.Eval.Context |
| symbolToShortText | |
| 1 (Function) | Howl.Symbol.Simple |
| 2 (Function) | Howl.Symbol.Symbolize, Howl.Symbol |