Etymology From earlier peake, peek, peke, from Middle English pek (in place names), itself an alteration of pike, pyke, pyk (“a sharp point, pike”), from Old English pīc, piic (“a pike, needle, pin, peak, pinnacle”), from Proto-West Germanic *pīk, from Proto-Germanic *pīkaz (“peak”). Cognate with Dutch piek (“pike, point, summit, peak”), Danish pik (“pike, peak”), Swedish pik (“pike, lance, point, peak”), Norwegian pik (“peak, summit”). More at pike.
A point; the sharp end or top of anything that terminates in a point; as, the peak, or front, of a cap.
A less risky method is to lift your whisk or beater to check the condition of the peaks of the egg whites; the foam should be just stiff enough to stand up in well-defined, unwavering peaks.2002, Joy of Cooking: All About Cookies, →ISBN, page 29:
2
The highest value reached by some quantity in a time period.
The stock market reached a peak in September 1929.
By last year, family income was 8 percent lower than it had been 11 years earlier, at its peak in 2000, according to inflation-adjusted numbers from the Census Bureau.2012 October 23, David Leonhardt, New York Times, retrieved 24 Oct 2012:
3
Geography, Natural sciences The top, or one of the tops, of a hill, mountain, or range, ending in a point.
They reached the peak after 8 hours of climbing.
4
Geography, Natural sciences The whole hill or mountain, especially when isolated.
To the South we observed a large plain some ten miles wide, with snowy peaks rising on the farther side. In front was a hill projecting into the plain, on which stood a mani wall; and this latter discovery made me feel quite confident that I was on the high road to Lhassa.1898, Arnold Henry Savage Landor, chapter 62, in In the Forbidden Land:
Etymology From earlier peake, peek, peke, from Middle English pek (in place names), itself an alteration of pike, pyke, pyk (“a sharp point, pike”), from Old English pīc, piic (“a pike, needle, pin, peak, pinnacle”), from Proto-West Germanic *pīk, from Proto-Germanic *pīkaz (“peak”). Cognate with Dutch piek (“pike, point, summit, peak”), Danish pik (“pike, peak”), Swedish pik (“pike, lance, point, peak”), Norwegian pik (“peak, summit”). More at pike.
Nautical, Transport To raise the point of (a gaff) closer to perpendicular.
2
Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences, Signal processing To exceed the maximum signal amplitude of (a piece of equipment), resulting in clipping of the signal.
3
To reach a highest degree or maximum.
Historians argue about when the Roman Empire began to peak and ultimately decay.
4
To rise or extend into a peak or point; to form, or appear as, a peak.
There peaketh up a mightie high mounte.1659, T[itus] Livius [i.e., Livy], “(please specify the book number)”, in Philemon Holland, transl., The Romane Historie […], London: […] W. Hunt, for George Sawbridge, […], →OCLC:
5
Of a person To reach the highest level of success or greatness in one's lifetime.
6
Of a person on drugs To reach the point of strongest effect from a drug.
7
Abbreviation, Ellipsis Ellipsis of peak trans.
Gender-critical slang
I came to this via sport but the thing that really peaked me was this.2019 August 4, Alison Weir (@WeirAlison), Twitter:
My friend peaked me last year, at the GRA [Gender Recognition Act] consultation.2019 August 31, MrsMiggins (@MrsMiggins13), Twitter:
1 more example
Solidarity from Spain, @jk_rowling. Thank you for peaking so many people all over the world.2021 November 22, DefendingMySisters (@DefendingMy), Twitter:
Etymology From earlier peake, peek, peke, from Middle English pek (in place names), itself an alteration of pike, pyke, pyk (“a sharp point, pike”), from Old English pīc, piic (“a pike, needle, pin, peak, pinnacle”), from Proto-West Germanic *pīk, from Proto-Germanic *pīkaz (“peak”). Cognate with Dutch piek (“pike, point, summit, peak”), Danish pik (“pike, peak”), Swedish pik (“pike, lance, point, peak”), Norwegian pik (“peak, summit”). More at pike.
1
At the greatest extent; maximum.
peak oil, Peak TV
2
Slang Maximal, quintessential, archetypical, strictly with positive connotations; representing the culmination of its type.
When they're tryna get the girl to the crib and she leaves, it's peak / Tryna keep it discreet and she tweets, it's peak / See me rolling with 20 man deep, it's peak / Yo rudeboy, pull up, repeat, it's peak2015, “Its Peak”, performed by Tinie Tempah (featuring Stormzy and Bugzy Malone):
Tempting, but I think it's actually something I need to do. Like, I get what they did was peak, but I have to take some responsibility, you know?2023, Nathan Bryon, Tom Melia, directed by Raine Allen-Miller, Rye Lane, spoken by Dom (David Jonsson):
[Siri:] Joz said, team, these apricots are peak. Have they always been this good? Why has no one told me?2026 June 8, Apple, 37:56 from the start, in WWDC 2026 Keynote:
peak
verb
Etymology Unknown. Perhaps related to Etymology 1 above in the sense of "becoming pointed" through emaciation.
1
To become sick or wan.
2
To acquire sharpness of figure or features; hence, to look thin or sickly.
Dwindle, peak, and pine.c. 1606 (date written), William Shakespeare, “The Tragedie of Macbeth”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene iii]: