Verb
To draw tighter; to straiten; to make more close in any manner.
Source: Webster's dictionarytighten the rules Source: Internet
stiffen the regulations Source: Internet
Tighten the wire Source: Internet
reduce the influx of foreigners Source: Internet
The rope tightened Source: Internet
A bill passed in the House to tighten background checks has not been brought for a vote in the Senate. Source: Internet