The most common and most likely answer to this crossword clue is the 6 plus 6 letter word MAIDEN VOYAGE
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More clues leading to the result MAIDEN VOYAGE
- But older women can also take this trip
- Any video game is unintelligible first time out
- Frenchman to support diplomat and get on initial trip?
- Cracking any video game in first excursion
- Female diplomat to get on first cruise
- Any video game’s ruined this trip
- Virgin Atlantic trip?
- and 16 Across: Journey, initially, taking servant and messenger long time
- Girl goes on a journey, her first
- Wacky diplomat takes time touring India on first overseas trip
Buddy explains!

The straight part
We know that "first overseas trip" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case first overseas trip = maiden voyage.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.