Profound, a.
Etymology: [F. profond, L. profundus; pro before, forward + fundus the bottom. See Found to establish, Bottom lowest part.]
1. Descending far below the surface; opening or reaching to a great depth; deep. "A gulf profound." Milton.
2. Intellectually deep; entering far into subjects; reaching to the bottom of a matter, or of a branch of learning; thorough; as, a profound investigation or treatise; a profound scholar; profound wisdom.
3. Characterized by intensity; deeply felt; pervading; overmastering; far-reaching; strongly impressed; as, a profound sleep. "Profound sciatica." Shak. Of the profound corruption of this class there can be no doubt. Milman.
4. Bending low, exhibiting or expressing deep humility; lowly; submissive; as, a profound bow. What humble gestures! What profound reverence! Dupp
3 other Webster entries under this spelling
Profound, n.
1. The deep; the sea; the ocean. God in the fathomless profound Hath all this choice commanders drowned. Sandys.
2. An abyss. Milton.
Profound, v. t.
To cause to sink deeply; to cause to dive or penetrate far down. [Obs.] Sir T. Browne.
Profound, v. i.
To dive deeply; to penetrate. [Obs.]
Shades of meaning
Fernald has no entry of its own for profound; he lists it under obscure.
Where he writes about it:
In that which is abstruse (L. abs, from, and trudo, push) as if removed from the usual course of thought or out of the way of apprehension or discovery, the thought is remote, hidden; in that which is obscure there may be nothing to hide; it is hard to see to the bottom of the profound, because of its depth, but the most shallow turbidness is obscure. — from obscure