Historic versus historical

Historic means "important," "momentous," or "historically significant."

Historical means "relating to the past."

Examples:

• "America has entered one of its periods of historic madness, but this is the worst I can remember." (John Le Carre)


• "The Sixties are now considered a historical period, just like the Roman Empire." (Dave Barry)
• Yesterday there was a historic event in Spain: the coronation of King Felipe VI.
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The event has historical significance because Felipe has become king while his father is still alive.