The highest point; the vertex: the apex of a triangle; the apex of a hill. (noun)
The point of culmination. See Synonyms at summit.(noun)
The usually pointed end of an object; the tip: the apex of a leaf. (noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "apex" in a sentence
"The breaking point, so to speak, of man's vision, that ecstasy of comprehension which I call his apex-thought, is the moment which makes him aware of these companions 'existence."
"However, if you a forty first experiment, and it tells you that the apex is somewhere wildly different in the picture, it would have told you that either you made some mistake, or that your assumption, that the standard model is the only source of CP violation, was incorrect."
"But his early work could be viewed as lacking in seriousness, and thus my choice for his apex is Americana, the 2001 volume that would be the last verse collection to appear under his name during his lifetime, anyway; I suspect we may see a posthumous collection."