verb (used with or without object), bifurcated, bifurcating. 1. to divide or fork into two branches. adjective. 2. divided into two branches.
Advertisement. By the Numbers. According to the National Sleep Foundation, newborns should sleep 12 to 18 hours out of every 24 (every new parent hopes), with a gradual reduction to 12 to 14 hours for toddlers ages 1 to 3; 11 to 13 hours for preschoolers 3 to 5; and (yes!) 10 to 11 hours for schoolchildren ages 5 to 10.
Most adults need between six and nine hours of sleep each night. Some people can feel perfectly rested with a lower amount. Newborn babies can sleep for 16 hours a day, while school age children need an average of 10 hours. Most people over the age of 70 tend to be light sleepers and need less than six hours a night.