Misname
/ˌmɪsˈneɪm/
Definition 1 of 1
Pro Tip 1/3Common Mistake
Often occurs when two names or terms are similar but refer to different things. 
She misnamed the capital of Australia as Sydney, not Canberra.
Pro Tip 2/3Cultural Sensitivity
Misnaming can offend, especially when related to personal or cultural identities. 
He was embarrassed after misnaming his classmate with a culturally significant name.
Pro Tip 3/3Accidental Usage
Misnaming is often unintentional, resulting from memory lapses or misinformation. 
Sorry for misnaming your brother as George; I thought that was his name.