<p><strong>Noun</strong></p><ul><li>the pointed top of a mountain or ridge.</li><li>a mountain with a pointed summit.</li><li>the pointed top of anything.</li><li>the highest or most important point or level: the peak of her political career.</li><li>the maximum point, degree, or volume of anything: Oil prices reached their peak last year.</li><li>a time of the day or year when traffic, use, demand, etc., is greatest and charges, fares, or the like are at the maximum: Early evening is the peak on commuter railroads.</li><li>a projecting point: the peak of a man's beard.</li><li>widow's peak.</li><li>the upper after corner of a sail that is extended by a gaff.</li><li>Nautical: the contracted part of a ship's hull at the bow or the stern.</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>to project in a peak.</li><li>to attain a peak of activity, development, popularity, etc.: The artist peaked in the 1950s.</li></ul><p><strong>Adjective</strong></p><ul><li>being at the point of maximum frequency, intensity, use, etc.; busiest or most active: Hotel rooms are most expensive during the peak travel seasons.</li><li>constituting the highest or maximum level, volume, etc.; optimal; prime: a machine running at peak performance.</li><li>being at the height of trendiness, public notice, etc.: We have reached peak “exercise dress.”</li><li>being the most perfect embodiment of something: Peak Gemini energy on display as our kid takes one lick off everyone’s cone, because she likes all the ice cream flavors.</li></ul>