Definitions

1. adjective

most strict or severe in punishing or condemning wrongdoers

“The judge was considered the chastest critic of the corrupt officials.”

2. adverb

in the severest or most severe manner

“The police officer chastest the drunk driver for his reckless behavior.”

3. verb

to punish or criticize severely

“The teacher chastest the student for his misbehavior.”