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.
Pre-school children require 10-13 hours a day. School-age children require 9-11 hours a day. Teenagers need about 8.5-9.5 hours on average. Most adults need 7 to 9 hours a night for the best amount of sleep, although some people may need as few as 6 hours or as many as 10 hours of sleep each day. Women in the first 3 months of pregnancy often need several more hours of sleep than usual.