Synonyms: thankless, ungrateful, unthankful
Definition: not feeling or showing gratitude
Usage: ungrateful heirs; How sharper than a serpent's tooth it is / To have a thankless child!- Shakespeare
Similar words: unappreciative
Definition: not feeling or expressing gratitude
Usage: unappreciative of nature's bounty
Synonyms: unappreciated, ungratifying, thankless
Definition: not likely to be rewarded
Usage: grading papers is a thankless task
Similar words: unrewarding
Definition: not rewarding; not providing personal satisfaction