means The highest point, surface, or part of something — or, as a noun, a spinning toy that stays upright only while it whirls.

from From Old English 'topp,' meaning the summit or crest of something, and shared across the Germanic family — cousins survive in Dutch 'top' and German 'Zopf' (a tuft or braid). The spinning-toy sense grew from the same idea of a point or crown, the bit that sits up high and turns. The clothing 'top' is much later, simply the garment for the upper half of the body.