toughen

v.

US //ˈtəfən// UK //tˈʌfən// tough·en

Origin

From tough + -en.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Idioms1 entry

01
toughen up
To make or become mentally tougher.

Last updated April 17, 2026

© 2026 English Reference