How many 14-letter words are there?

5,127 in the Tournament dictionary, which is the public-domain ENABLE word list. The Broad dictionary adds more.

What is the highest-scoring 14-letter word?

QUIZZICALITIES at 43 points, counting tile values with no board multipliers.

No. The page shows the 300 highest-scoring; the pages linked below break the full list down by starting and ending letters.

5,127 words are exactly 14 letters long. QUIZZICALITIES scores highest at 43 points.

Showing the highest-scoring of 5,127 words. The pages linked below split the rest into smaller lists.

14-letter words number 5,127 in all. Below is the high-scoring end of that list, with links to narrower pages underneath.

From 14 letters to 14: the 14-letter band is the densest with 5,127 words, and the 14-letter band the scarcest with 5,127.

The highest-scoring answer is QUIZZICALITIES at 43 points in Scrabble. It tops both tables: 46 in Words With Friends as well.

At 14 letters, QUIZZICALITIES, SUBJECTIVIZING and BENZIMIDAZOLES are as long as this set goes.

To go further, put a few of these letters into the solver above and filter by length.

benzodiazepine: any of several similar lipophilic amines used as tranquilizers or sedatives or hypnotics or muscle relaxants
hypophysectomy: surgical removal of the pituitary gland
demythologized: having mythical elements removed
philosophizing: the exposition (often superficially) of a particular philosophy
brachycephalic: an adult with a short broad head

How many 14-letter words are there?: 5,127 in the Tournament dictionary, which is the public-domain ENABLE word list. The Broad dictionary adds more.
What is the highest-scoring 14-letter word?: QUIZZICALITIES at 43 points, counting tile values with no board multipliers.
Are all of them listed here?: No. The page shows the 300 highest-scoring; the pages linked below break the full list down by starting and ending letters.