From ancient times peculiar virtue was attributed to fire thus obtained, which was supposed to have great efficacy in overcoming the enchantment to which disease, such as that of cattle, was ascribed. The superstition survived in the Highlands of Scotland until a recent date. [Century Dictionary]
early 14c., clogge "a lump of wood," origin unknown. Also used in Middle English of large pieces of jewelry and large testicles. Compare Norwegian klugu "knotty log of wood." Meaning "anything that impedes action" is from 1520s, via the notion of "block or mass constituting an encumbrance."
The sense of "wooden-soled shoe" is first recorded late 14c.; they were used as overshoes until the introduction of rubbers c. 1840. Originally all of wood (hence the name), later wooden soles with leather uppers for the front of the foot only. Later revived in fashion (c. 1970), primarily for women. Clog-dancing "dancing performed in clogs" is attested from 1863.
c. 1400, "a box," especially, in Church use, the vessel in which the host or consecrated bread is kept, from Latin pyxis, from Greek pyxis "box-wood; a box" (originally one made of box-wood), from pyxos "box-wood; box-tree," a word of uncertain origin, perhaps a loan-word from Italy, where the tree is native.
In nautical use from 1680s as "the metal box in which the compass is suspended." Hence also Pyxis as the name of a Southern constellation proposed 1760s by Lacaille (along with Puppis, Carina, and Vela) to be made from parts of the unwieldy ancient Argo, though Malus "mast" also was long used for this part.