Definition of natural disaster : a sudden and terrible event in nature (such as a hurricane, tornado, or flood) that usually results in serious damage and many deaths The earthquake was one of the worst natural disasters of this century.
Synthesis, Chemical. the planned production of complex compounds from simpler compounds based on a knowledge of the reactantsâ chemical structure and reactivity. Chemical synthesis usually implies a sequence of several chemical processes (steps). In the early period in the development of chemistry, chemical synthesis was carried out mainly for inorganic compounds and was fortuitous in nature.
5 (Chem). a (of a molecule or compound) being or having a molecule in which there is an uneven distribution of electrons and thus a permanent dipole moment. water has polar molecules. b (of a crystal or substance) being or having a crystal that is bound by ionic bonds.