1. 绷紧(或:上紧)一点：Unleash the drilling tools. 卸开钻具 | Tighten up. 绷紧(或:上紧)一点 | Turn on the cooling water for the windlasses. 开锚机刹车冷却水

2. 使紧密：tighten the screws 加强控制 | tighten up 使紧密 | tighten 变紧

3. 拉紧：tight-strong seam 强固紧密焊缝 | tighten up 拉紧 | tighten 收紧

verb

1. restrict

e.g. Tighten the rules
stiffen the regulations

Synonym: stiffentightenconstrain