tightens up

Verb

tighten up (third-person singular simple present tightens up, present participle tightening up, simple past and past participle tightened up)

1. (transitive) To make sufficiently tight.
2. (transitive) To fix something or make it correct.
   • As noted in the last chapter, you should tighten up your argument and prose when you revise the first draft for substantive change.2012, Stanley Chodorow, Gordon Harvey, Writing a Successful Research Paper, and, Writing with Sources, →ISBN
3. (intransitive) To become tense and restrained.
   • You must follow every change because every change affects your play. If another player loses a big pot, you must ask yourself how this will affect his play. Will he go on tilt? Will he tighten up?2006, David Apostolico, Lessons From The Pro Poker Tour, →ISBN
4. (intransitive, transitive) To become, or make, more stringent and ungenerous.
   • In May 1973 Honecker made another speech to the SED Central Committee, in which he appeared to want to tighten up the rules, as if his remarks in 1971 had been interpreted too liberally, but the VIIth Writers' Congress in November of the same year confirmed the relative freedom of the previous two...1997, Pól Ó Dochartaigh, The Portrayal of Jews in GDR Prose Fiction, →ISBN, page 153
5. (intransitive) To become focused and serious; to stop any vacillation or inconsistency.
   • Plainly winter was at hand.
     "Just as well we started when we did," said Bill. "No tellin' when she'll tighten up."
     "May do it any time," Sam agreed.1922, A. M. Chisholm, A Thousand a Plate