1 syllable words instead of ugly?

Here are some one-syllable words that could replace "ugly," depending on the nuance you want to convey:

* Homely: Suggests plainness, not conventionally attractive.

* Plain: Simple and unadorned.

* Grim: Suggests harshness or unpleasantness.

* Mean: Suggests unpleasantness in appearance or character.

* Harsh: Similar to grim.

* Bad: A general negative term.

The best replacement will depend on the context.