Henry in confidence gives strong push (6)
I believe the answer is:
thrust
'strong push' is the definition.
'thrust' can be an answer for 'push' (synonyms). I'm unsure of the 'strong' bit.
'henry in confidence' is the wordplay.
'henry' becomes 'H' (symbol for the unit of electrical inductance).
'in' means one lot of letters goes inside another.
'confidence' becomes 'trust' (synonyms).
'h' put into 'trust' is 'THRUST'.
'gives' is the link.
Can you help me to learn more?
(Other definitions for thrust that I've seen before include "Force producing motion" , "Sudden lunge or attack" , "force in argument" , "Sudden lunge (of sword)" , "Push forward as with sword or spear" .)