anonymously
adverb
UK/əˈnɒn.ɪ.məs.li/
US/əˈnɑː.nə.məs.li/
Definitions of anonymously adverb
in a way that does not reveal one's identity or name; without being identified by name.
She donated a large sum of money to the charity anonymously.
The whistleblower chose to provide information anonymously.
They sent threatening letters anonymously.