Webster's Revised Unabridged Dictionary · 1913

Phantasm

Phantasm , noun

[Latin phantasma. See Phantom, and compare Fantasm.]

1.
An image formed by the mind, and supposed to be real or material; a shadowy or airy appearance; sometimes, an optical illusion; a phantom; a dream.
They be but phantasms or apparitions. — Sir W. Raleigh
2.
A mental image or representation of a real object; a fancy; a notion. — Cudworth
Figures or little features, of which the description had produced in you no phantasm or expectation. — Jer. Taylor