To make harsh or rugged; to add harshness to (language, sounds, etc.); to render (laws) more severe. Obsolete.

To make sharp or sharper (in various transferred and figurative senses of the adjective). Now… To increase the severity of (a law, a punishment…

To render more strict or rigorous. Obsolete.

intransitive. To grow tight or tense; to be stretched tight or drawn close. Frequently const. up. Also figurative.