Handshake perhaps is one welcome when introducing people (9)
I believe the answer is:
agreement
'handshake perhaps is one' is the definition.
I can't judge whether this definition defines the answer.
'welcome when introducing people' is the wordplay.
I cannot really see how this works, but
'people' could be 'men' (men are people) and 'men' is found within the answer.
'welcome' could be 'greet' (to greet someone is to welcome them) and 'greet' is found within the remaining letters.
A single letter 'a' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for agreement that I've seen before include "consensus" , "deal" , "Unlikely result" , "Pact" , "concert" .)