What does it mean when you lose part of the power to your house?

My husband was screwing an outdoor lightbulb into the socket of a motion light outside our house. He said there was a buzzing sound and then the lights went out along some of the wall outlets in our house and two bedrooms. Flipping the breakers has not worked. Then when we were plugging something into one of the walls that does have electricity to the outlets one of the bedroom lights flickered.