IUPAC definition : A molecular entity formed by loose association involving two or more component molecular
entities (ionic or uncharged), or the corresponding chemical species. The bonding
between the components is normally weaker than in a covalent bond. The term has also
been used with a variety of shades of meaning in different contexts: it is therefore
best avoided when a more explicit alternative is applicable. In inorganic chemistry
the term 'coordination entity' is recommended instead of 'complex'.;
A molecular entity formed by loose association involving two or more component molecular
entities (ionic or uncharged), or the corresponding chemical species. The bonding
between the components is normally weaker than in a covalent bond. The term has also
been used with a variety of shades of meaning in different contexts: it is therefore
best avoided when a more explicit alternative is applicable. In inorganic chemistry
the term 'coordination entity' is recommended instead of 'complex'.