I. ˈtərshēˌerē, ˈtə̄sh-, ˈtəish-, -eri also -shər- noun
( -es )
Etymology: in sense 1, from Medieval Latin tertiarius, from Latin, of or containing a third; in other senses from tertiary (II)
1. : a member of a monastic third order after the first order of monks and the second order of nuns composed of men and women of the laity who take no more than simple vows, who may remain outside of a monastery and hold property, and yet who follow to some degree a portion of a monastic rule
Franciscan and Dominican tertiaries
2. : a tertial feather
3. usually capitalized : the Tertiary period or system of rocks
4. : tertiary color
5.
a. : a lesion of tertiary syphilis
b. : tertian 1
II. adjective
Etymology: Latin tertiarius of or containing a third, from tertius third + -arius -ary — more at third
1.
a. : third in order or importance : preceded by two others
a tertiary characteristic
a few transformers are provided … with a tertiary winding — J.B.Gibbs
a tertiary cambium develops around a number of the secondary elements — Ernst Artschwager
b. : of or relating to a monastic third order
c. : of or relating to education following the secondary level whether at a college or university or at an intermediate institution
d. : of or relating to the service industries (as distribution, transportation, domestic service) compared with agriculture or manufacturing
e. : of, relating to, or constituting the third strongest of the three or four degrees of stress recognized by most linguists
the third syllable in basketball's fun carries the tertiary stress
f. : tertial
2. usually capitalized : of or relating to the time interval between the close of the Mesozoic era and the beginning of the Quaternary period during which the Alps, Caucasus, Himalayas, and other high mountains were formed, the Cordilleran system from Alaska to Cape Horn was developing, and the dominant land life was mammalian — see geologic time table
3. : characterized by replacement in the third degree : resulting from the substitution of three atoms or groups in a molecule
a tertiary salt
tertiary phosphates
especially : being or characterized by a carbon atom united by three valences to chain or ring members
tertiary butyl (CH 3 ) 3 C
— compare primary 5, secondary 2e
4. : occurring or being in the third stage
tertiary lesions of syphilis
III. adjective
1. : being or relating to the recovery of oil and gas from old wells by means of the underground application of heat and chemicals
2. : being or relating to the purification of wastewater by removal of fine particles, nitrates, and phosphates
3. : providing tertiary care
a tertiary medical center