v (transitive|+ partitive) To
address sb (especially the elderly and people with higher social status) with the second-person
'plural
' form of the personal pronoun in a polite or formal manner (in languages
'where that person is distinguishable from the second-person singular
'); (
the equivalent in English customs:) to
address a person by her/his
last name (with or without her/his
professional title).