See more synonyms for activity on
noun, plural ac·tiv·i·ties.
  1. the state or quality of being active: There was not much activity in the stock market today. He doesn't have enough physical activity in his life.
  2. a specific deed, action, function, or sphere of action: social activities.
  3. work, especially in elementary grades at school, that involves direct experience by the student rather than textbook study.
  4. energetic activity; animation; liveliness.
  5. a use of energy or force; an active movement or operation.
  6. normal mental or bodily power, function, or process.
  7. Physical Chemistry. the capacity of a substance to react, corrected for the loss of reactivity due to the interaction of its constituents.
  8. Physics.
    1. the number of atoms of a radioactive substance that disintegrate per unit of time, usually expressed in curies.
    2. radioactivity.
  9. an organizational unit or the function it performs.

Origin of activity

1520–30; (< Middle French) < Medieval Latin āctīvitās. See active, -ity
Related formsnon·ac·tiv·i·ty, noun, plural non·ac·tiv·i·ties.pre·ac·tiv·i·ty, noun, plural pre·ac·tiv·i··per·ac·tiv·i·ty, noun, plural su·per·ac·tiv·i·ties. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for activities

Contemporary Examples of activities

Historical Examples of activities

  • Of Rouquet's activities as an artist in England there are scant particulars.

  • Among my other activities, I wired the parlor for electric light.


    Mary Roberts Rinehart

  • I followed him about while he arranged for the termination of the day's activities.

  • Barbara was helping him, at least she called her activities "helping."


    Joseph C. Lincoln

  • They discussed the village and the people in it and the church and its activities.

    Kent Knowles: Quahaug

    Joseph C. Lincoln

British Dictionary definitions for activities


noun plural -ties
  1. the state or quality of being active
  2. lively action or movement
  3. any specific deed, action, pursuit, etcrecreational activities
  4. the number of disintegrations of a radioactive substance in a given unit of time, usually expressed in curies or disintegrations per second
    1. the capacity of a substance to undergo chemical change
    2. the effective concentration of a substance in a chemical system. The absolute activity of a substance B, λ B, is defined as exp (μ B RT) where μ B is the chemical potential
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for activities

in schoolwork sense, 1923, American English, from activity.



c.1400, "active or secular life," from Old French activité, from Medieval Latin activitatem (nominative activitas), a word in Scholastic philosophy, from Latin activus (see active). Meaning "state of being active, briskness, liveliness" recorded from 1520s; that of "capacity for acting on matter" is from 1540s.

Online Etymology Dictionary, © 2010 Douglas Harper

activities in Medicine


  1. A physiological process.
  2. The presence of neurogenic electrical energy in electroencephalography.
  3. An ideal concentration for which the law of mass action will apply perfectly.
  4. The intensity of a radioactive source.
  5. The ability to take part in a chemical reaction.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.