It's the opposite. Bull markets are when price starts to increase. Bear markets are when price starts to decline.
Years ago, I had an amazing macroeconomics professor named Alex Kelly. Dr. Kelly was an amazing educator with an incredible sense of humour, a penchant for telling the truth as he saw it, and genuine glee when he'd see students start to understand his material.
I'll never forget the class where Dr. Kelly stood up, did his impression of a bear standing on his hind legs, growling and pushing down the market. Then showing the converse, snorting like a bull and pushing up the market.
Afterwards, he did his usual shrug, reached into his pocket to fish out his everpresent Rolaids, quipped "now if anyone gets that wrong on the midterm..." and shook his head menacingly.
Dr. Kelly could flat out teach and I quote him to this day.