BACK-UP, BACK UP
NOUNS
1990 ► ASSIST back-up, usually in the form of physical power → sl.
NOUNS, PERSON
1990 ► ASSIST the person drawn in to provide back-up → sl.
VERBS
1970 ► BACK SOMEONE’S PLAY to back up the statements or actions of another person → US sl.
Lexicophilia 