ungrateful

Not grateful; not expressing gratitude.

Near-synonyms: unappreciative, unthankful

“It seems to delight you to think that you are to leave Paris, and that we shall not see each other for months, perhaps. Tarzan, you are a most ungrateful beast!” and D’Arnot laughed.

Disagreeable, repellent, unpleasant.

If any care for what is here ⁠Survive in spirits render’d free, ⁠Then are these songs I sing of thee Not all ungrateful to thine ear.

A person who fails to show gratitude; an ingrate.