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mark; guide; landmark
purpose; aim; goal; intention; end
sight (on a firearm)
目当ての本を見つけた。
I found the book I was looking for.
彼は出世を目当てに会社に入った。
He joined the company with the aim of career advancement.
多くの観光客は美しい紅葉を目当てにその山を訪れている。
Many tourists visit that mountain with the aim of seeing the beautiful autumn leaves.