A man is an adult male human. In older or more general use, 'man' can also mean a human being in general, though this use is now often avoided to be more inclusive.
From Old English 'mann', which originally meant 'person' or 'human being', not specifically male. Only over centuries did it narrow in everyday speech to mean an adult male.
Historically, 'man' meant 'human', which is why we see it inside words like 'mankind', 'manual', and 'manufacture'. Knowing this explains a lot of older texts that seem to talk only about men when they actually meant all people.
In English, "man" historically served both as a gender-neutral term for a human and as a male-specific term, which contributed to centering men as the default humans in law, philosophy, and everyday speech. Phrases like "mankind" and generic "man" have been used to describe all people while implicitly erasing women and non-binary people.
Use "man" only when specifically referring to an adult male individual. For generic or collective references to humans, use gender-neutral terms like "person," "people," "humankind," or "humanity."
["person","individual","people","human","humanity","humankind"]
Women and non-binary people’s contributions to "mankind’s" achievements have often been subsumed under male-coded language, which made it easier to overlook their specific roles in science, politics, art, and daily labor.
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