The most common and most likely answer to this crossword clue is the 8 letter word OUTGOING
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More clues leading to the result OUTGOING
Buddy explains!

The straight part
We know that "retiring/friendly and sociable" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case retiring/friendly and sociable = outgoing.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does OUTGOING mean?
OUTGOING verb- To go out, to set forth.
- To go further; to exceed or surpass; go beyond.
- To overtake; to travel faster than.
- To outdo; exceed; surpass.
- To come to an end.
- The act of leaving or going out; exit, departure.
- (chiefly in the plural) Money that leaves one's possession; expenditure, outlay, expense.
- The extreme limit; the place of ending.
- Extraverted: talkative, friendly, and social, especially with respect to meeting new people easily and comfortably.
- Going out, on its way out.
- Being replaced in office (while still in office but after election has determined that he/she will be replaced).