noun
A specific assignment or purpose one is sent to accomplish, often with a sense of importance or duty.
彼は秘密の使命を帯びて海外へ赴いた。
He went abroad on a secret mission.
noun
A broader sense of a role or responsibility one feels compelled to fulfill, not necessarily a single dispatched assignment.
医師としての使命を果たす。
Fulfill one's duty as a doctor.