Definition of vacuous:
lunkheaded, pinheaded, undiscriminating, impulsive, empty, unfilled, dumb, stark, dense, thick, airheaded, waste, empty-bellied, oafish, clean, mindless, shallow, dim-witted, dim, unsmart, inane, meaningless, untenanted, hasty, asinine, slow, dunderheaded, ill-considered, white, obtuse, simple, thick-witted, thickheaded, fatuous, soft, irresponsible, weak-minded, senseless, clear, bonehead, witless, reasonless, drained, dorky, full, lamebrain, boneheaded, half-witted, knuckleheaded, softheaded, brain-dead, unemployed, bubbleheaded, toom, birdbrained, bare, unintelligent, depleted, forgetful, chuckleheaded, opaque, leisure, doltish, gormless, impetuous, unmindful, foolish, hollow, dopey, slow-witted.
- dumb (part of speech: adjective)
- thoughtless (part of speech: adjective)
- unsubstantial (part of speech: adjective)
- nonexistent (part of speech: adjective)
- "War and the Weird", Forbes Phillips R. Thurston Hopkins.
- "Precipitations", Evelyn Scott.
- "Masterman and Son", W. J. Dawson.