a. 1. Slippery; changeable. [ Obs. ] [ 1913 Webster ]

My love is glibbery; there is no hold on't. Marston. [ 1913 Webster ]

2. Moving easily; nimble; voluble. [ Obs. ] [ 1913 Webster ]

Thy lubrical and glibbery muse. B. Jonson. [ 1913 Webster ]

n. [ From Gib to balk. ] A balky horse. Youatt. [ 1913 Webster ]

v. i. [ imp. & p. p. gibbered p. pr. & vb. n. gibbering. ] [ Akin to jabber, and gabble. ] To speak rapidly and inarticulately. Shak.
Syn. -- jabber. [ 1913 Webster ]

n. (Chem.), A plant growth hormone of the gibberellin series (C19H22O6), also called gibberellin A₃. It was first isolated from the fungus Gibberella fujikuroi. It is used to promote the growth of seedlings. See also gibberellin. MI11 [ PJC ]

n. (Chem.), Any of a number plant growth hormones, the first of which was isolated in 1938 from the fungus Gibberella fujikuroi; more than 60 related gibberelins are known. The most important is gibberellin A₃, also called gibberellic acid. They are used in agriculture for promoting plant growth. [ WordNet 1.5 +PJC ]

a. Unmeaning; as, gibberish language. [ 1913 Webster ]

n. [ From Gibber, v. i. ] 1. Rapid and inarticulate talk; unintelligible language; unmeaning words. [ 1913 Webster ]

He, like a gypsy, oftentimes would go;
All kinds of gibberish he had learnt to know. Drayton. [ 1913 Webster ]

Such gibberish as children may be heard amusing themselves with. Hawthorne. [ 1913 Webster ]

2. Incomprehensible, obscure, or pretentious technical talk or writing; excessively obscure jargon. [ PJC ]