Friendly lad displacing new guy to embrace one (8)
I believe the answer is:
sociable
'friendly' is the definition.
('sociable' can be a synonym of 'friendly')
'displacing new guy to embrace one' is the wordplay.
'displacing new' becomes 'so' (I can't justify this - if you can you should believe this answer much more).
'guy' becomes 'cable' (I've seen this in other clues).
'to embrace' means one lot of letters goes inside another.
'one' becomes 'i' (Roman numeral).
'cable' going around 'i' is 'ciable'.
'so'+'ciable'='SOCIABLE'
'lad' acts as a link.
This may not be right. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for sociable that I've seen before include "Companionable, friendly" , "Friendly - gregarious" , "Friendly and pleasant" , "Fond of mixing with others" , "Marked by friendliness" .)