For physical etching:
* Smooth: The surface was once etched, but it has now been smoothed.
* Unmarked: The glass was unmarked, unlike the other one which had been etched.
* Blank: The blank metal plate was ready to be etched.
For metaphorical etching:
* Forgotten: The memory of the event was deeply etched in his mind, but now it has been forgotten.
* Faded: The image of her childhood home was etched in her memory, but now it has faded with time.
* Indelible: The experience was deeply etched in his mind, and it remained indelibly imprinted.
For art or design:
* Uncarved: The wood block was uncarved, unlike the one that had been intricately etched.
* Plain: The plain fabric lacked the intricate etchings of the other one.
* Undecorated: The undecorated surface was a stark contrast to the one with intricate etchings.
The best antonym for "etched" will depend on the specific meaning and context of the word.