pentavalentadj.
/ˌpɛntəˈveɪlənt/, /ˌpɛntəˈveɪln̩t/, U.S. /ˌpɛn(t)əˈveɪl(ə)nt/ Chemistry.
Having a valency of five. Cf. quinquevalent adj. and n.
ΘΚΠ
the world > matter > chemistry > valency > [adjective] > having a valency of five
pentatomic1858
pentavalent1866
quinquevalent1866
1866 J. A. R. Newlands in Chem. News 18 May 229/2 By separating the atoms x x to a still greater extent, the element would successively become bivalent, trivalent, quadrivalent, pentavalent, and finally when the atoms were completely sundered, hexavalent.
1906 H. J. H. Fenton Notes Qualitative Anal. (new ed.) 8 Compounds of pentavalent arsenic in solution always contain the arsenic in the acidic part or anion.
1978 H. M. Rosenberg Solid State (ed. 2) ix. 148 Energy levels which are associated with the presence of tri- and pentavalent impurities are called shallow states.
2001 N. Jones Rough Guide Trav. Health ii. 272 A 10-day intravenous course of pentavalent antimony (sodium stibogluconate) is partially effective but side effects require specialist monitoring.
This entry has been updated (OED Third Edition, September 2005; most recently modified version published online March 2022).
<
adj.1866