Meaning

• To demand and enforce the payment or performance of, sometimes in a forcible or imperious way.

  "to exact tribute, fees, or obedience from someone"

• To make desirable or necessary.

• To inflict; to forcibly obtain or produce.

  "to exact revenge on someone"

Meaning

• Making excessive demands; difficult to satisfy.

• (of an action, task, etc) Requiring precise accuracy, great care, effort, or attention.

• (of a person or organization) Characterized by exaction.