profound

adjective
1

Descending far below the surface; opening or reaching to great depth; deep.

2

Very deep; very serious.

3

Intellectually deep; entering far into subjects; reaching to the bottom of a matter, or of a branch of learning; thorough.

"a profound investigation"

4

Characterized by intensity; deeply felt; pervading.

5

Bending low, exhibiting or expressing deep humility; lowly; submissive.

noun
1

The deep; the sea; the ocean.

2

An abyss.

verb
1

To cause to sink deeply; to cause to dive or penetrate far down.

2

To dive deeply; to penetrate.

Source: https://en.wiktionary.org/wiki/profound

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