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to disappear into; to be lost in; to slip into; to get mixed in among
to do something under the cover of (confusion, etc.)
to be almost indistinguishable; to be confusingly similar
to be diverted from (negative emotions, etc.); to forget about
to be distracted by; to be too absorbed in
追っ手から逃れるため彼は大勢の群衆に紛れて逃げた。
He escaped by blending into the crowd.
締め切り前の忙しい仕事に紛れて休憩の時間を忘れていた。
I forgot about time while absorbed in work.
大切な書類が他の紙に紛れてしまった。
Important documents got mixed up with other papers.