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


adjective cu·mu·la·tive \ˈkyü-myə-lə-tiv, -ˌlā-\

Simple Definition of cumulative

  • : increasing or becoming better or worse over time through a series of additions

  • : including or adding together all of the things that came before

Full Definition of cumulative

  1. 1 a :  made up of accumulated parts b :  increasing by successive additions

  2. 2 :  tending to prove the same point <cumulative evidence>

  3. 3 a :  taking effect upon completion of another penal sentence <a cumulative sentence> b :  increasing in severity with repetition of the offense <cumulative penalty>

  4. 4 :  formed by the addition of new material of the same kind <a cumulative book index>

  5. 5 :  summing or integrating overall data or values of a random variable less than or less than or equal to a specified value <cumulative normal distribution> <cumulative frequency distribution>

cu·mu·la·tive·ly adverb
cu·mu·la·tive·ness noun

Examples of cumulative

  1. … Game Boy, which first came out in 1989 as a monochrome handheld toy, has become the most successful of all of the systems, reaching cumulative sales of 110 million units to date … —N'gai Croal, Newsweek, 28 May 2001

  2. They began looking at the cumulative effect of stress and realized that, while there might have been an incident that finally triggered the madness, a series of previous events had lowered the soldier's emotional resistance. —Michael Fleming and Roger Manvell, Psychology Today, July 1987

  3. Insist on yourself; never imitate. Your own gift you can present every moment with the cumulative force of a whole life's cultivation; but of the adopted talent of another, you have only an extemporaneous, half possession. —Ralph Waldo Emerson, “Self-Reliance,” in Essays, 1841

  4. <a cumulative weight gain of 20 pounds over the course of a year>

Origin of cumulative

(see cumulate)

First Known Use: 1605

Medical Dictionary


adjective cu·mu·la·tive \ˈkyü-myə-lət-iv, -ˌlāt-\

Medical Definition of cumulative

  1. :  increasing in effect by successive doses (as of a drug or poison) <cumulative poisoning by organochlorine pesticides—Jack Clincy>

  2. cu·mu·la·tive·ly adverb

Seen and Heard

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


February 9, 2016

marked by high spirits and laughter

Get Word of the Day daily email!


Take a 3-minute break and test your skills!


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

kittly-benders duvet spindrift pince-nez
Name That Thing

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


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