καταστέλλωkatastéllō

to put down, i.e. quell

Greek (New Testament) · G2687

Meanings

1. to let down, lower.

2. to keep down, restrain: with accusative, Acts 19:35, Acts 19:36.

Same root

κατάkatá · G2596(prepositionally) down (in place or time), in varied relations (according to the case (genitive, dative or accusative) with which it is joined)
στέλλωstéllō · G4724properly, to set fast ("stall"), i.e. (figuratively) to repress (reflexively, abstain from associating with)
καταστολήkatastolḗ · G2689a deposit, i.e. (specially) costume

Where it appears

Appears 2 times in the Bible.

Acts 19:35 At last the mayor was able to quiet them down enough to speak. “Citizens of Ephesus,” he said. “Everyone knows that Ephesus is the official guardian of the temple of the great Artemis, whose image fell down to us from heaven.
Acts 19:36 Since this is an undeniable fact, you should stay calm and not do anything rash.

Source: G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922), public domain.