Baby jogger (noun):
An informal term for a jogging stroller — a type of baby stroller designed with sturdy construction and large wheels so it can be pushed while jogging or running with a child inside. It’s built to handle rougher terrain and faster movement better than a regular stroller. The term originally came from the brand Baby Jogger, which made one of the first popular jogging-style strollers.

• It means a jogging stroller, a stroller fit for running or fast walking.

• Designed to be more stable and easier to push over uneven surfaces than regular strollers.

• The phrase comes from usage and from a stroller brand name that became a generic term.

If you want, I can also give you synonyms or how to use the term in a sentence!