ascetic, acetic

Ascetic or ascetic means someone who gives up physical luxuries and comforts for religious reasons--
He studied religious philosophy and became  an ascetic.
Ascetic also describes an austere lifestyle, without comforts or luxuries--
His diet was ascetic. He ate almost nothing but bran and spinach.

Acetic or acetic ( rhymes with ascetic ) means something that can make or be made from vinegar--
The scientific name for household vinegar is acetic acid.
Wine can be used to make acetic acid.

Now that you know that, you can say--
"The ascetic sometimes used plain acetic acid as a salad dressing."

Note--not to be confused with "aesthetic" ( ess thet ick ), used to describe what is connected to an idea of beauty--
It's practical, but it doesn't have any aesthetic appeal.