### Clue: Promised choice of two or three headings (5)
### Answer: SWORN 
 ### Explanation: Definition: Promised
 [SW(abbrev. for "south-west") OR N(abbrev. for "north")](choice of two headings;compass directions); or
[ S(abbrev. for "south"), W(abbrev. for "west") OR N(abbrev. for "north")](choice of three headings).