A positive response to a request or a favor, implying that in order to fulfill the request or favor you must first put aside the banana you are eating. Example: Hey, Roy, can I borrow your leather chaps for tonight's ice cream social? Let me set my 'nana down.
SET MY 'NANA DOWN
Meaning of SET MY 'NANA DOWN in English
Slang English vocab. Английский сленговый словарь. 2012