Answer:
Lewis Carroll originally defined brillig in this way:
BRYLLIG: (derived from the verb to bryl or broil). "the time of broiling dinner, i.e. the close of the afternoon"

A definition reiterated by Humpty Dumpty in Through the Looking Glass:
`there are plenty of hard words there. "Brillig" means four o'clock in the afternoon -- the time when you begin broiling things for dinner.'
First answer by MisoSoup. Last edit by MisoSoup. Contributor trust: 104 [recommend contributor recommended]. Question popularity: 7 [recommend question].