If an ion contains more than one atom, even if these atoms are of the same element, it is called a polyatomic ion.
When this rule is broken, giving the molecule a charge, the result is sometimes named a molecular ion or a polyatomic ion.
Sulfur (which borders the diatomic nonmetals), is the least metallic of the polyatomic nonmetals but even here shows some discernible metal-like character (discussed below).
When the group of covalently bound atoms bears a net charge, the group is referred to more properly as a polyatomic ion or a complex ion.
For more complex polyatomic molecules, the situation is more difficult.