Definify.com

Webster 1913 Edition

Verb.

[

Ugly

-fy

To disfigure; to make ugly.

[R.]

Mad. D’Arblay.

uglify ‎(third-person singular simple present uglifies, present participle uglifying, simple past and past participle uglified)

(transitive) To make ugly; to destroy or worsen the appearance or attractiveness of.
(intransitive) To become ugly.
- 1986, Piers Anthony, Golem in the Gears:
  Inevitably those bodies age and uglify under her influence, but if they are outstandingly beautiful at the outset, that process takes longer.

to make ugly