Jack giving king new greeting (5)
I believe the answer is:
knave
'jack' is the definition.
(knave can mean a jack playing card)
'giving king new greeting' is the wordplay.
'giving' says to put letters next to each other.
'king' becomes 'K' (abbreviation for king in chess).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'greeting' becomes 'ave' (Latin greeting).
'k'+'n' is 'kn'.
'kn'+'ave'='KNAVE'
(Other definitions for knave that I've seen before include "Jack - rogue" , "pack member?" , "A swindler" , "geezer" , "Honour" .)