| stiffen | (verb) become stiff or stiffer | - |
|---|
| (verb) make stiff or stiffer | - |
| (verb) severely restrict in scope or extent | Synonyms: constrain, tighten, tighten up |
| stifle | (verb) suppress or constrain so as to lessen in intensity | Synonyms: dampen |
|---|
| (verb) be asphyxiated; die from lack of oxygen | Synonyms: asphyxiate, suffocate |
| (verb) suppress in order to conceal or hide | Synonyms: muffle, repress, smother, strangle |
| (verb) impair the respiration of or obstruct the air passage of | Synonyms: asphyxiate, choke, suffocate |