noun ter·tia·ry \ˈtər-shē-ˌer-ē, -shə-rē\
plural ter·tia·ries

Definition of TERTIARY

[Medieval Latin tertiarius, from Latin, of a third] :  a member of a monastic third order especially of lay people
capitalized :  the Tertiary (see 2tertiary)period or system of rocks

First Known Use of TERTIARY

circa 1550

Other Geology Terms

anthracite, boulder, cwm, erratic, igneous, intrusive, mesa, sedimentary, silt, swale

Rhymes with TERTIARY

actuary, adversary, airy-fairy, ancillary, antiquary, apiary, arbitrary, aviary, axillary, bacillary, beriberi, bestiary, biliary, black raspberry, Bloody Mary, boysenberry, breviary, budgetary, calamari, calamary, candleberry, Canterbury, capillary, carpellary, cassowary, catenary, cautionary, cavitary, cemetery, centenary, certiorari, checkerberry, chinaberry, cometary, commentary, commissary, condottiere, coralberry, corollary, coronary, culinary, customary, dictionary, dietary, dignitary, dromedary, dysentery, elderberry, emissary, estuary, farkleberry, February, formulary, fragmentary, fritillary, functionary, funerary, honorary, huckleberry, intermarry, janissary, January, lamasery, lapidary, lectionary, legendary, legionary, lingonberry, literary, loganberry, luminary, mammillary, mandatary, maxillary, medullary, mercenary, miliary, military, millenary, milliary, millinery, missionary, momentary, monastery, mortuary, necessary, ordinary, ossuary, partridgeberry, pensionary, pigmentary, planetary, Pondicherry, prebendary, presbytery, pulmonary, quaternary, red mulberry, reliquary, rowanberry, salivary, salmonberry, salutary, sanctuary, sanguinary, sanitary, secondary, secretary, sedentary, seminary, silverberry, solitary, sour cherry, stationary, stationery, statuary, subcontrary, sublunary, sugarberry, sumptuary, syllabary, temporary, thimbleberry, Tipperary, Tom and Jerry, topiary, tributary, tutelary, Typhoid Mary, unitary, urinary, vestiary, Virgin Mary, visionary, voluntary, vulnerary, Waterbury, whortleberry, winterberry


adjective ter·tia·ry \ˈtər-shē-ˌer-ē, -shə-rē\

: third in order, importance, or value

Full Definition of TERTIARY

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 (as the stress of the third syllable of basketball team)
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 (as the Alps, Caucasus, and Himalayas) and the dominance of mammals on land — see geologic time table
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
:  occurring in or being a third stage: 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

Examples of TERTIARY

  1. Headaches often occur during the tertiary stage of the illness.
  2. 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

Origin of TERTIARY

Latin tertiarius of or containing a third, from tertius third
First Known Use: circa 1656


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