also acknowledgement /ɪkˈnɑːlɪʤmənt/
Learner's definition of ACKNOWLEDGMENT
1 : the act of acknowledging something or someone: such as a : the act of showing that you know, admit, or accept that something exists or is true
The killer's apology was an acknowledgment [=admission] of his guilt. = The killer's apology was an acknowledgment that he was guilty.
The day passed without any acknowledgment that it was their wedding anniversary. [=no one mentioned that it was their wedding anniversary]
They made several public acknowledgments of their company's mistake.
[noncount] b : the act of praising or thanking someone for an action or achievement
2 acknowledgments [plural] : a section of a book, article, etc., in which people are thanked for their help 3 [count] : a usually written statement saying that a letter or message was received