argentum, = white metal; silver;
-eum, = indicates material or colour or resemblance in quality.
argenteus, = of or from silver, made of silver; of a white, silver colour, silvery.
(silvery) (ld, BL)
caput, = of things; the head, top, summit, point, end, extremity;
-ulus, -ellus, = diminutive;
capitulum, = a small head;
-atus, = indicates possession or likeness.
capitulatus, = having or ending in a small head. (ld, BL)