adverb
absent overseas; out of the country
Used to indicate that someone is currently away on an overseas trip, often for official or business purposes. The 中 suffix emphasizes the ongoing state.
社長は外遊中で、来週まで戻りません。
The president is out of the country and won't return until next week.
外遊中はメールでの対応となります。
While I am abroad, I will handle matters by email.