Bedeutung von “tighten sth up” — Learner’s Dictionary

tighten sth up

phrasal verb with tighten us uk /ˈtaɪtən/ verb [ I, T ]

to make something become firmer and less easy to move:

Tighten up the screws.

(Definition von “tighten sth up phrasal verb, verb” aus dem Cambridge Learner's Dictionary © Cambridge University Press)