mutable

American  

[myoo-tuh-buhl] / ˈmyu tə bəl /

adjective

1. liable or subject to change or alteration.

   Synonyms:

   variable, changeable

2. given to changing; constantly changing; fickle or inconstant.

   the mutable ways of fortune.

   Synonyms:

   unsteady, unsettled, vacillating, unstable

   Antonyms:

   stable

3. Computers. (in object-oriented programming) of or noting an object having properties whose values can change while the object itself maintains a unique identity.

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mutable British  

/ ˈmjuːtəbəl /

adjective

1. able to or tending to change

2. astrology of or relating to four of the signs of the zodiac, Gemini, Virgo, Sagittarius, and Pisces, which are associated with the quality of adaptability Compare cardinal fixed

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Other Word Forms

• hypermutable
  adjective
• hypermutably
  adverb
• mutability
  noun
• mutableness
  noun
• mutably
  adverb
• nonmutable
  adjective
• nonmutably
  adverb
• unmutable
  adjective

Etymology

Origin of mutable

First recorded in 1350–1400; Middle English, from Latin mūtābilis, equivalent to mūtā(re) “to change” + -bilis -ble

Explanation

Something or someone that is mutable is subject to change. Mutable weather can go from sunny, to rainy and windy, and back to sunny again. The word mutable originally had a negative connotation, and it referred to a person, usually a poet, who frequently changed his mind and moods. Mutable has come to mean anything that is capable of changing form or quality. If your favorite restaurant offers seasonal food, the menu is probably mutable with the change in seasons. In science, the word mutable refers to an organism or a gene that, for better or worse, changes its form.

Example Sentences

Mr. Picton’s approach to structure is aggressively mutable, but his arrangements are almost entirely acoustic.

From The Wall Street Journal • Apr. 14, 2026

Still, “It showed that those sites are mutable in these viruses,” says Tom Peacock, an influenza virologist at the Pirbright Institute.

From Science Magazine • Dec. 5, 2024

But when you take a step backwards and you look at the gameplay, a station wagon is mutable.

From Seattle Times • Feb. 20, 2024

Because of this I suspect its allegorical potency will be perceived as a bit too mutable.

From Salon • Jun. 23, 2023

Only the waters are ours; and how may one build on something so mutable?

From "The Astonishing Life of Octavian Nothing, Traitor to the Nation, Volume II: The Kingdom on the Waves" by M.T. Anderson