1911 Encyclopædia Britannica/Cob
COB, a word of unknown origin with a variety of meanings, which the New English Dictionary considers may be traced to the notions of something stout, big, round, head or top. In “cobble,” e.g. in the sense of a round stone used in paving, the same word may be traced. The principal uses of “cob” are for a stocky strongly built horse, from 13 to 14 hands high, a small round loaf, a round lump of coal, in which sense “cobble” is also used, the fruiting spike of the maize plant, and a large nut of the hazel type, more commonly known as the cob-nut.
“Cobbler,” a patcher or mender of boots and shoes, is probably from a different root. It has nothing to do with an O. Fr. coubler, Mod. coupler, to fasten together. In “cobweb,” the web of the spider, the “cob” represents the older cop, coppe, spider, cf. Dutch spinnekop.