The Only Use of

sententious
in
Great Expectations

But he presently presented himself under worthier circumstances; for, the Genius of Youthful Love being in want of assistance,—on account of the parental brutality of an ignorant farmer who opposed the choice of his daughter's heart, by purposely falling upon the object, in a flour-sack, out of the first-floor window,—summoned a sententious Enchanter; and he, coming up from the antipodes rather unsteadily, after an apparently violent journey, proved to be Mr. Wopsle in a high-crowned hat, with a necromantic work in one volume under his arm.†
p. 407.5

Definition:

annoying attempt to sound smart or important

or more rarely (and typically in classic literature):

expressing wisdom or knowledge concisely