tertiary

1 of 2

adjective

ter·​tia·​ry ˈtər-shē-ˌer-ē  -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

c

: of, relating to, or being the normal folded structure of the coiled chain of a protein or of DNA or RNA

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

tertiary

2 of 2

noun

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.

Recent Examples on the Web

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

Word History

Etymology

Adjective

Latin tertiarius of or containing a third, from tertius third

First Known Use

Adjective

circa 1656, in the meaning defined at sense 1a

Noun

circa 1550, in the meaning defined at sense 1

Phrases Containing tertiary

• tertiary care
• tertiary color
• tertiary education
• tertiary syphilis

Kids Definition

tertiary

1 of 2 adjective

ter·​ti·​ary

ˈtər-shē-ˌer-ē

1

: of third rank, importance, or value

2

capitalized : of, relating to, or being the earliest period of the Cenozoic era of geological history marked by the formation of high mountains (as the Alps and Himalayas) and the rise in importance of mammals on land

also : relating to the corresponding system of rocks see geologic time

Tertiary

2 of 2 noun

: the Tertiary period or system of rocks

Medical Definition

tertiary

1 of 2 noun

ter·​tia·​ry ˈtər-shē-ˌer-ē  ˈtər-shə-rē 

plural tertiaries

1

: tertiary color

2

: a lesion of tertiary syphilis

tertiary

2 of 2 adjective

1

: 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