See Also: sphero-(medicine)
sphero-(dictionary)

nontronite (iou) and sphero- (iou)


nontronite (iou)



nontronite noun. M19.
[from Nontron a town in France + -ITE1.]
Mineralogy. A pale yellow or greenish crystalline clay mineral of the montmorillonite group, sometimes resembling opal. Also called chloropal.

sphero- (iou)



sphero- combining form.
[Var. of SPHAERO-, alt. after SPHERE noun, or directly from SPHERE noun + -O-.]
Spherical or partly spherical in form; having or consisting of spherical parts; pertaining to spheres.
sphero-cy'lindrical adjective (of a lens) having a spherical and a cylindrical surface L19.
spherograph noun (Nautical) a device designed to facilitate the calculation of spherical problems M19.
sphe'rometer noun an instrument for measuring the sphericity or curvature of bodies or surfaces E19.
spheroplast noun (Biology) a bacterium or plant cell bound by its plasma membrane, the cell wall being deficient or lacking and the whole having a spherical form M20.
spheroplasting verbal noun treatment (as with an enzyme) that converts cells to spheroplasts M20.