There is no prefix in the word deep, and there are no non-hyphenated prefixes.
There are hyphenated compound adjectives such as skin-deep and knee-deep.
The archaic term undeep meant "very far below the ground or surface."
High, deep.
Ultramarine is deep blue; blue color is redundant.
Prefix=IN
The prefix for inadequate is in-. The prefix in- means not.
The prefix for include is in-. This prefix means not.
Yes, prefix does have a prefix. The prefix is pur-.
Demi has no prefix; it IS a prefix.
The prefix is in-. This prefix means not.
The prefix is in-. This prefix means not.
The prefix is micro.
The prefix is in. The prefix in- means not.
prefix