orthodontics

noun

or·​tho·​don·​tics ˌȯr-thə-ˈdän-tiks How to pronounce orthodontics (audio)
plural in form but singular in construction
: a branch of dentistry dealing with irregularities of the teeth (such as malocclusion) and their correction (as by braces)
also : the treatment provided by a specialist in orthodontics
orthodontic adjective
orthodontically adverb
orthodontist noun

Word History

First Known Use

1909, in the meaning defined above

Time Traveler
The first known use of orthodontics was in 1909

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Cite this Entry

“Orthodontics.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/orthodontics. Accessed 5 Sep. 2025.

Kids Definition

orthodontics

noun
orth·​odon·​tics
ˌȯr-thə-ˈdänt-iks
: a branch of dentistry dealing with faults in the arrangement and placing of teeth and with their correction (as by means of braces)
orthodontic
-ˈdänt-ik
adjective

Medical Definition

orthodontics

noun, plural in form but singular in construction
orth·​odon·​tics -ˈdänt-iks How to pronounce orthodontics (audio)
1
: a branch of dentistry dealing with irregularities of the teeth and their correction (as by means of braces)
2
: the treatment provided by an orthodontist
orthodontic adjective
orthodontically adverb

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