Coercion (6)
'coercion' is the definition.
(under duress means being coerced)
This is the entire clue.
(Other definitions for duress that I've seen before include "Threats, violence, etc, used in coercion" , "Coercion, compulsion" , "Compulsion by use of force" , "Illegal coercion" , "Hardship" .)
(Other definitions for drive that I've seen before include "Trip in car - road to house" , "Road off main highway" , "offensive" , "Control and steer vehicle" , "Private road; impel" .)
(Other definitions for clasp that I've seen before include "Close hands round" , "Fastening - firm grip" , "Part of a necklace" , "Grip firmly" , "Catch hold" .)
'coercion' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for force that I've seen before include "Physical strength" , "fall" , "Powerful effect or influence" , "Violence" , "Muscle" .)