Word of honor (7)
'word of honor' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for vow that I've seen before include "Promise, swear" , "Plight" , "Pledge, take oath" , "Binding promise" , "Solemn pledge" .)
'word of honor' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for promise that I've seen before include "Vow" , "Guarantee" , "Hope; commitment" , "Hopeful sign" , "Cause for hope" .)