tighten up tighten one's belt • tightener · · · Info · Definitions · Synonyms · Characters · · tighten up · · Text Common · · Latin · · Scripts 10 · · Length 3 · · Syllables Definitions · · · (verb) restrict. Synonyms: stiffen, tighten, tighten up, constrain. Examples: "Tighten the rules." "Stiffen the regulations." · · Verb Definition 1 Synonyms · · · stiffen · · Synonym 1 tighten · · Synonym 2 constrain · · Synonym 3 Characters · · space U+0020 e latin small letter e U+0065 g latin small letter g U+0067 h latin small letter h U+0068 i latin small letter i U+0069 n latin small letter n U+006E p latin small letter p U+0070 t latin small letter t U+0074 u latin small letter u U+0075