The phrase "to wear to work" means to put on or don clothing that is appropriate for a professional environment, typically clothes that are neat and clean. It refers to getting dressed in attire suitable for going to one's place of employment.
Usage examples
Casual dress: A comfortable pair of jeans with a button-down shirt is a great outfit to wear to work on casual Fridays.
Business professional attire: A tailored suit, paired with a crisp dress shirt and a tie, is the perfect choice to wear to work when attending important meetings or presentations.
Business casual look: Slacks or dress pants with a blazer and a nicely ironed dress shirt can be a stylish and professional outfit option to wear to work on a regular basis.
Smart casual outfit: A blouse combined with a pair of tailored pants or a skirt, along with some accessories, strikes the perfect balance between casual and formal and can be a great choice to wear to work.
Dressy attire: A sophisticated dress or a skirt suit is appropriate to wear to work on special occasions or when attending professional events.
I've already worn it to work on several really hot days this summer and I love how you feel light and breezy but still manage to look quite dressed at the same time! (caliope-couture.com)
I love the longer sleeves, perfect for wearing to work with a skirt. (ladyinviolet.com)