Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

Medical Dictionary

1

focus

play
noun fo·cus \ˈfō-kəs\

Medical Definition of focus

plural fo·ci \ˈfō-ˌsī also -ˌkī\play play also fo·cus·es

  1. 1a:  a point at which rays (as of light, heat, or sound) converge or from which they diverge or appear to diverge; specifically :  the point where the geometrical lines or their prolongations conforming to the rays diverging from or converging toward another point intersect and give rise to an image after reflection by a mirror or refraction by a lens or optical systemb:  a point of convergence of a beam of particles (as electrons)

  2. 2a:  focal lengthb:  adjustment for distinct vision; also :  the area that may be seen distinctly or resolved into a clear image

  3. 3:  a localized area of disease or the chief site of a generalized disease or infection




2

focus

verb fo·cus

Medical Definition of focus

fo·cused also fo·cussedfo·cus·ing also fo·cus·sing

  1. transitive verb

  2. 1:  to bring (as light rays) to a focus

  3. 2a:  to adjust the focus of (as the eye or a lens)b:  to bring (as an image) into focus

  4. intransitive verb

  5. 1:  to come to a focus

  6. 2:  to adjust one's eye or a camera to a particular range

  7. fo·cus·able \-kəs-ə-bəl\play adjective





Seen and Heard

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

WORD OF THE DAY

February 6, 2016

an official order, decree, or edict

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

image1037863653

Which of the following refers to thin, bending ice, or to the act of running over such ice?

spindrift pince-nez kittly-benders duvet
Name That Thing

10 quick questions: hear them, spell them, and see how your skills compare to the crowd.

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ