titanousadj.
/ˈtʌɪtənəs/, U.S. /ˈtaɪtn̩əs/ Containing titanium; Chemistry forming names of compounds or salts in which the element has an oxidation state of +3; of or relating to titanium in this oxidation state. Contrasted with titanic adj.2 2.
ΘΚΠ
the world > matter > chemistry > elements and compounds > metals > specific elements > titanium > [adjective] > containing
titaniferous1813
titanous1849
1849 H. Watts tr. L. Gmelin Hand-bk. Chem. III. 469 The resulting black mass is probably, therefore, a mixture of titanic acid with titanous oxide [Ger. Titanoxydul].
1868 H. B. Jones & H. Watts Fownes's Man. Elem. Chem. (ed. 10) 449 Titanous fluoride..is obtained as a violet powder by igniting potassio-titanic fluoride in hydrogen gas.
1906 H. J. H. Fenton Notes Qualitative Anal. (new ed.) 169 Titanous salts are usually violet and are powerful reducing agents.
1955 Internat. Financial News Surv. 7 374/2 There is reason to believe that Norway has the largest titanous iron ore fields in Europe.
1970 Science 30 Jan. 583/1 This may be explained either by the presence of some of the titanium in the titanous state or by interference in the ferrous iron titration.
2000 J. E. Earley et al. in E. T. Urbansky Perchlorate in Environment ix. 90 Titanous ion (Ti3+), ruthenous ions (Ru2+) and some Mo iii species all reduce perchlorate ion in aqueous media.
Compounds
titanous oxide n. titanium( iii) oxide, Ti2O3.
ΚΠ
1866 H. E. Roscoe Lessons Elem. Chem. xxiii. 206 The oxides of titanium correspond to those of tin; viz. titanous and titanic oxides.
1868 H. Watts Dict. Chem. V. 842 Titanous oxide dissolves in acids, forming violet solutions.
1975 Carbohydrate Res. 44 293 An aqueous suspension of hydrous titanous oxide.
1991 Colloids & Surfaces 61 98 The dark-colored hydrous titanous oxide formed was then oxidized to the white titanic form by bubbling oxygen gas through the suspensions.
This entry has been updated (OED Third Edition, January 2018; most recently modified version published online March 2022).
<
adj.1849