ter·tia·ry
ˈtər-shē-ˌer-ē 
-shə-rē
-shə-rē
1
a
: of third rank, importance, or value
b
chiefly British
: of, relating to, or being higher education
c
: of, relating to, or constituting the third strongest of the three or four degrees of stress recognized by most linguists (such as the stress of the third syllable of basketball team)
2
capitalized
: of, relating to, or being the first period of the Cenozoic era or the corresponding system of rocks marked by the formation of high mountains (such as the Alps, Caucasus, and Himalayas) and the dominance of mammals on land see Geologic Time Table
3
a
: involving or resulting from the substitution of three atoms or groups
a tertiary salt
tertiary amine
b
: being or containing a carbon atom having bonds to three other carbon atoms
an acid containing a tertiary carbon
tertiary alcohols
4
: occurring in or being a third stage: such as
a
: being or relating to the recovery of oil and gas from old wells by means of the underground application of heat and chemicals
b
: being or relating to the purification of wastewater by removal of fine particles, nitrates, and phosphates
plural tertiaries
1
[Medieval Latin tertiarius, from Latin, of a third]
: a member of a monastic third order especially of lay people
2
capitalized
: the Tertiary (see tertiary entry 1 sense 2) period or system of rocks
Examples of tertiary in a Sentence
Adjective
Bill Clinton … has passed through the tertiary and quaternary stages and is well on his way to millenary integrity.
—
Cullen Murphy, Atlantic, January/February 2003
A tertiary care doctor at a cushy academic medical center, a plastic surgeon, and a dentist in a Pleasantville suburb don't spend much time taking care of poor patients who lack basic insurance.
—Siddhartha Mukherjee, New Republic, 17 Sept. 2001
The most learned philosopher knew little more. He had partially unveiled the face of Nature, but her immortal lineaments were still a wonder and a mystery. He might dissect, anatomise, and give names; but, not to speak of a final cause, causes in their secondary and tertiary grades were utterly unknown to him.
—Mary Wollstonecraft Shelley, Frankenstein, 1818
Headaches often occur during the tertiary stage of the illness.
Cullen Murphy, Atlantic, January/February 2003
A tertiary care doctor at a cushy academic medical center, a plastic surgeon, and a dentist in a Pleasantville suburb don't spend much time taking care of poor patients who lack basic insurance.
—Siddhartha Mukherjee, New Republic, 17 Sept. 2001
The most learned philosopher knew little more. He had partially unveiled the face of Nature, but her immortal lineaments were still a wonder and a mystery. He might dissect, anatomise, and give names; but, not to speak of a final cause, causes in their secondary and tertiary grades were utterly unknown to him.
—Mary Wollstonecraft Shelley, Frankenstein, 1818
Headaches often occur during the tertiary stage of the illness.
Recent Examples on the Web
Jeetendr Sehdev, Forbes, 30 Sep. 2024
This has significant long-term secondary and tertiary consequences.
—Ariel Cohen, Forbes, 23 Sep. 2024
Michael Middlehurst-Schwartz, USA TODAY, 24 Mar. 2020
See all Example Sentences for tertiary 
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Adjective
Produced by 20th Television, The Simpsons has entertained audiences not just with its regular characters like Bart Simpson, Lisa Simpson, and Grampa Simpson, but also with tertiary characters who contribute to the richness of its world.
—Jeetendr Sehdev, Forbes, 30 Sep. 2024
This has significant long-term secondary and tertiary consequences.
—Ariel Cohen, Forbes, 23 Sep. 2024
Noun
The Texans paid handsomely for a player whose career was revived in part due to serving as a tertiary option and operating out of the slot.
—Michael Middlehurst-Schwartz, USA TODAY, 24 Mar. 2020
See all Example Sentences for tertiary
Dictionary Entries Near tertiary
Cite this Entry
“Tertiary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tertiary. Accessed 25 Nov. 2024.
Copy CitationMedical Definition
tertiary
1 of 2 noun
ter·tia·ry
ˈtər-shē-ˌer-ē
ˈtər-shə-rē
ˈtər-shə-rē
plural tertiaries
1
2
: a lesion of tertiary syphilis
tertiary
2 of 2 adjective1
: of third rank, importance, or value
2
a
: involving or resulting from the substitution of three atoms or groups
a tertiary salt
b
: being or containing a carbon atom having bonds to three other carbon atoms
an acid containing a tertiary carbon
c
: of, relating to, or being the normal folded structure of the coiled chain of a protein or of a DNA or RNA compare primary entry 1 sense 4, secondary sense 3
3
: occurring in or being a third stage
tertiary lesions of syphilis
4
: providing tertiary care
a tertiary medical center
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