Labelling, christening (6)
I believe the answer is:
naming
I believe this is a double definition.
'labelling' is the first definition.
(naming is a kind of labelling)
'christening' is the second definition.
(I've seen this before)
(Other definitions for naming that I've seen before include "Allotting term to" , "Christening" , "Conferring appellation on" , "Calling" , "Identifying, citing" .)