noun \ ˈā-ˌpeks \
|Updated on: 4 Aug 2018

Definition of apex

plural apexes or apices play \ˈā-pə-ˌsēz, ˈa-\
1 a : the uppermost point : vertex
  • the apex of a mountain
b : the narrowed or pointed end : tip
  • the apex of the tongue
2 : the highest or culminating point
  • the apex of his career
3 : the point of sharpest curvature in a path (such as that followed by a turning vehicle)
  • a driver hitting the apex as he races around a corner
  • At the apex of the turn his rear wheels apparently came unstuck from the oil-drenched groove.
  • —Robert F. Jones

apex was our Word of the Day on 02/27/2010. Hear the podcast!

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

Recent Examples of apex from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'apex.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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 and Etymology of apex


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 English Language Learners


Definition of apex for English Language Learners

  • : the top or highest point of something

APEX Defined for Kids


noun \ ˈā-ˌpeks \

Definition of apex for Students

plural apexes or apices \ˈā-pə-ˌsēz\
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 : 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 play \ˈā-pə-ˌsēz\
: a narrowed or pointed end of an anatomical structure: as
a : the narrow somewhat conical upper part of a lung extending into the root
b : 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 side
c : the extremity of the root of a tooth

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