Definitions

1. verb

the second person singular present subjunctive of will; used to express a wish, command, or request

“Thou wouldst be a better friend if thou helped me.”

2. auxiliary verb

used to express a wish, command, or request in the past tense

“He wouldst have come if he had known.”

3. past subjunctive

used to express a hypothetical or contrary-to-fact situation

“If I were you, I wouldst not do that.”