The definition of an ingrate is a person who is ungrateful.
(noun)A friend who stays at your house for a month and then leaves without so much as a "thank you," is an example of an ingrate.
See ingrate in Webster's New World College Dictionary
adjective
Origin: ME ingrat < OFr < L ingratus, unpleasant, ungrateful < in-, not + gratus, grateful: see grace
noun
See ingrate in American Heritage Dictionary 4
noun
Origin:
Origin: From Middle English ingrat, ungrateful
Origin: , from Old French
Origin: , from Latin ingrātus
Origin: : in-, not; see in-1
Origin: + grātus, pleasing, thankful; see gwerə-2 in Indo-European roots
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