combining form on Gr. models of L. vitrum glass, used in a few terms, as vitro-de·ntine, the hard external layer of dentine in a tooth; vi·trophyre, a subdivision of porphyritic rocks; hence vitrophyric adj.; vi·trotype (see quot. 1875).
1849–52. Todd’s Cycl. Anat., IV. 882/1. The dental plate consists … of a central mass of coarse osseous substance … and an external sheath of very hard ‘vitro-dentine.’
1870. trans. Stricker’s Man. Histology, xv. (N. Syd. Soc.), 471. The central portion [of a tooth] consists of vaso-dentine, which is covered with true dentine; external to which again is a thin layer of vitro-dentine.
1875. Knight, Dict. Mech., 2713/2. Vitro-type (Photography), a name given to the processes which involve the production of collodion film pictures on glass.
1882. Geikie, Text-Bk. Geol., II. II. iii. 90. Vogelsang has proposed to classify this type [Porphyritic] in three divisions: 1st, Granophyre,… 2nd, Felsophyre,… 3rd, Vitrophyre, where the ground-mass is a glassy magna.
1890. Philos. Mag., March, 288. Among the pyroxenic rocks the most noticeable varieties are the labradorite-audesites, the pyroxene-audesites—of which both ‘trachytoid’ and ‘vitrophyric’ forms occur.
