Water is a transparent and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms. Its chemical formula is H2O, meaning that its molecule contains one oxygen and two hydrogen atoms, that are connected by covalent bonds.
1. recently born; called also neonatal. 2. newborn infant. postmature newborn (post-term newborn) post-term infant. premature newborn (preterm newborn) preterm infant.
A Neonatal Intensive Care Unit (NICU) is a hospital unit which is dedicated to the care of very ill infants. Most commonly, an infant is sent to the NICU because he or she is premature, and prone to an assortment of health problems.