1831, "pertaining to or characteristic of John Locke" (1632-1704), greatest of the English metaphysicians. The surname means one with fine curls or else one who lives near, or operates, a canal lock.
1670s, "of or pertaining to the French," from Latin Gallicus "pertaining to Gaul or the Gauls," from Latin Gallia "Gaul" and Gallus "a Gaul" from a native Celtic name (see Gaelic), though some connect the word with prehistoric West Germanic *walkhoz "foreigners" (see Welsh). Originally used in English rhetorically or mockingly for "French." The cock as a symbol of France is based on the pun of Gallus "a Gaul" and Latin gallus "cock" (see gallinaceous). Earlier was Gallican (1590s).
It means not simply 'French,' but 'characteristically', 'delightfully', 'distressingly', or 'amusingly' 'French' ... not 'of France', but 'of the typical Frenchman'. [Fowler]
As "of or pertaining to the ancient Gauls" from 1796.
"of great antiquity or age," 1809, from Greek Ōgygos, Ōgygēs, Ōgygios, name of a mythical king of Attica or Boeotia (or both) of whom nothing is known and who even in classical times was thought to have lived very long ago. Also sometimes with reference to a famous flood said to have occurred in his day.