The definition of apologize means to admit you know you did something wrong and to seek forgiveness or express your wish that you hadn't done it.(verb)
To send someone a card that says you are upset over your past actions is an example of apologize.
See apologize in Webster's New World College Dictionary
See apologize in American Heritage Dictionary 4
intransitive verb a·pol·o·gized, a·pol·o·giz·ing, a·pol·o·giz·es
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