Warning or hint (6)
I believe this is a double definition.
'warning' is the first definition.
(I've seen this before)
'hint' is the second definition.
(thesaurus)
I believe this is a double definition.
'warning' is the first definition.
(I've seen this before)
'hint' is the second definition.
(thesaurus)
(Other definitions for tip-off that I've seen before include "Confidential warning" , "Give advance warning or hint" , "Give a secret warning" , "Warn in advance" , "Confidential hint" .)