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verb os·si·fy \ˈä-sə-ˌfī\

Simple Definition of ossify

  • : to become or to cause something to become unable to change

  • : to become or to cause something to become hard like bone

Source: Merriam-Webster's Learner's Dictionary

Full Definition of ossify



  1. intransitive verb
  2. 1 :  to change into bone

  3. 2 :  to become hardened or conventional and opposed to change

  4. transitive verb
  5. 1 :  to change (as cartilage) into bone

  6. 2 :  to make rigidly conventional and opposed to change

Examples of ossify in a sentence

  1. The cartilage will ossify, becoming bone.

  2. a disease that ossifies the joints

Did You Know?

The skeletons of mammals originate as soft cartilage that gradually transforms into hard bone (in humans, the process begins in the womb and continues until late adolescence). English speakers have referred to this bone-building process as "ossification" since the late 17th century, and the verb "ossify" arrived soon after the noun. English speakers began to use "ossification" and "ossify" for more figurative types of hardening (such as that of the heart, mind, or soul) in the 19th century. Both words descend from the Latin root os, meaning "bone." "Os" is also an English word that appears in scientific contexts as a synonym of "bone," and the Latin term is an ancestor of the word osseous, which means "consisting of or resembling bone."

Origin and Etymology of ossify

Latin oss-, os + English -ify

First Known Use: 1713

Rhymes with ossify

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Medical Dictionary


verb os·si·fy \ˈäs-ə-ˌfī\

Medical Definition of ossify




  1. intransitive verb

  2. :  to form or be transformed into bone <cartilage ossified postnatally>

  3. transitive verb

  4. :  to change (as cartilage) into bone <osteoblasts ossify the tissue>

Seen and Heard

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


of, relating to, or near a shore

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