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Synonyms

inactive

American  
[in-ak-tiv] / ɪnˈæk tɪv /

adjective

  1. not active.

    an inactive volcano.

    Synonyms:
    inoperative, immobile, unmoving
    Antonyms:
    lively
  2. sedentary or passive.

    an inactive life.

    Antonyms:
    lively
  3. sluggish; indolent.

    Synonyms:
    slothful, idle, lazy
    Antonyms:
    lively
  4. Military. not on active duty.

  5. Chemistry.

    1. inert; unreactive.

    2. noting a compound that has no effect on polarized light.


inactive British  
/ ɪnˈæktɪv /

adjective

  1. idle or inert; not active

  2. sluggish, passive, or indolent

  3. military of or relating to persons or equipment not in active service

  4. chem (of a substance) having little or no reactivity

  5. (of an element, isotope, etc) having little or no radioactivity

"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

Related Words

Inactive, dormant, inert, sluggish, torpid suggest lack of activity. Inactive indicates absence of action, indisposition to activity, or cessation of activity: an inactive compound, life, file of papers. Dormant suggests the quiescence or inactivity of that which sleeps but may be roused to action: a dormant volcano. Inert suggests the condition of dead matter, with no inherent power of motion or action; it may also mean unable to move, or heavy and hard to move: an inert mass; inert from hunger. Sluggish expresses slowness of natural activity or of that which does not move readily or vigorously: a sluggish stream, brain. Torpid suggests a state of suspended physical powers, a condition particularly of animals that hibernate: Snakes are torpid in cold weather.

Other Word Forms

  • inactively adverb
  • inactiveness noun
  • inactivity noun

Etymology

Origin of inactive

First recorded in 1715–25; in- 3 + active

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

By mapping glucose's chemical path inside the cell, the researchers identified clear differences between inactive sperm and those that had been activated.

From Science Daily

Berkshire was relatively inactive in the first three quarters of 2025.

From Barron's

Most comets native to our solar system remain relatively inactive that far out.

From Science Daily

For many years, scientists assumed that each cyst housed a single, uniform type of parasite that remained inactive until it reawakened.

From Science Daily

"But it requires balance. Neurons need to be active or inactive at the right times. If that rhythm goes out of sync even a little bit, it can change the function of the entire brain."

From Science Daily