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noun, \ˈā-ˌpeks\

Simple Definition of apex

  • : the top or highest point of something

Source: Merriam-Webster's Learner's Dictionary

Full Definition of apex

plural apexes or apicesplay \ˈā-pə-ˌsēz, ˈa-\

  1. 1 a :  the uppermost point :  vertex <the apex of a mountain> b :  the narrowed or pointed end :  tip <the apex of the tongue>

  2. 2 :  the highest or culminating point <the apex of his career>

Examples of apex in a sentence

  1. <she reached the apex of fame, only to find it wasn't what she expected>

  2. <the apex of the spear>

Did You Know?

Apex entered English from Latin, where it originally meant "a small rod at the top of a flamen's cap." What's a flamen's cap? Flamens were priests who devoted themselves to serving just one of the many ancient Roman gods (for instance, just Jupiter or Mars). Those priests wore distinctive conical caps that English speakers dubbed "flamen's caps." Sixteenth- and seventeenth-century dramatist Ben Jonson was one of the few English writers known to have used "apex" in its flamen's-cap sense: "Upon his head a hat of delicate wool, whose top ended in a cone, and was thence called apex."

Origin of apex


First Known Use: 1601

Synonym Discussion of apex

summit, peak, pinnacle, climax, apex, acme, culmination mean the highest point attained or attainable. summit implies the topmost level attainable <at the summit of the Victorian social scene>. peak suggests the highest among other high points <an artist working at the peak of her powers>. pinnacle suggests a dizzying and often insecure height <the pinnacle of worldly success>. climax implies the highest point in an ascending series <the war was the climax to a series of hostile actions>. apex implies the point where all ascending lines converge <the apex of Dutch culture>. acme implies a level of quality representing the perfection of a thing <a statue that was once deemed the acme of beauty>. culmination suggests the outcome of a growth or development representing an attained objective <the culmination of years of effort>.

APEX Defined for Kids


noun \ˈā-ˌpeks\

Definition of apex for Students

plural apexes or apices \ˈā-pə-ˌsēz\

  1. 1 :  the highest point :  peak <“She's on top of the roof, walking with a foot either side of the apex …” — Brian Jacques, Redwall>

  2. 2 :  the most successful time <He was at the apex of his career.>

Medical Dictionary


noun \ˈā-ˌpeks\

Medical Definition of apex

plural apexes or apices \ˈā-pə-ˌsēz\play

  1. :  a narrowed or pointed end of an anatomical structure: asa:  the narrow somewhat conical upper part of a lung extending into the rootb:  the lower pointed end of the heart situated in humans opposite the space between the cartilages of the fifth and sixth ribs on the left sidec:  the extremity of the root of a tooth

Seen and Heard

What made you want to look up apex? Please tell us where you read or heard it (including the quote, if possible).


a timid, meek, or unassertive person

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