Ungratefulness is an antonym of gratefulness.
As nouns the difference between ungratefulness and gratefulness
is that ungratefulness is the state of being ungrateful while gratefulness is the state of being grateful.
gratefulness
English
Noun
(-)
The state of being grateful
Synonyms
* gratitude
* thankfulness
Antonyms
* ungratefulness
* ingratitude
* unthankfulness