A deepity is a proposition that seems both important and true—and profound—but that achieves this effect by being ambiguous. On one reading it is manifestly false, but it would be earth-shaking if it were true; on the other reading it is true but trivial. The unwary listener picks up the glimmer of truth from the second reading, and the devastating importance from the first reading, and thinks, Wow! That’s a deepity.
Example: Love is just a word.
“love” is an English word, but just a word, not a sentence, for example.
Source:
Philosopher Daniel Dennett’s Book Intuition Pumps
