Meaning of COMPLEX in English
in chemistry, a substance, either an ion or an electrically neutral molecule, formed by the union of simpler substances (as compounds or ions) and held together by forces that are chemical (i.e., dependent on specific properties of particular atomic structures) rather than physical. The formation of complexes has a strong effect on the behaviour of solutions. See also chemical association; coordination compound.
Britannica English vocabulary. Английский словарь Британика. 2012