1.VerbTo watch or tend someone else's child for a period of time, often for money.
"My daughter is babysitting for the Morgans at number ten, who are going out on a date night.; We need someone to babysit our children while we go to the theater."
2.VerbTo watch or tend a thing or process without normally intervening in it, e.g. as a precaution should an emergency happen.
"The reaction takes several hours, so we leave a graduate student to babysit it."
3.VerbTo watch or attend anything or anyone more closely than ought to be needed; to have to help or coax too much.
"He left me to babysit the new guy while he got some work done."