A quantifier is a non-affixal form that provides information on the quantity of a set of objects or an amount of substance.
The most widely discussed quantifiers in linguistics are universal quantifiers ('all', 'every') and existential quantifiers ('one', 'some'), but languages also frequently use mid-scale quantifiers ('several', 'many'), and cardinal numerals are typically regarded as quantifiers as well (e.g. Keenan & Paperno 2012). (However, Croft (2022) does not include them.) ❡
In logic, "quantifier" has a different sense, referring to formal operators such as ∀ and ∃, and this sense sometimes influences the way linguists use the term.
quantifier (CXN) = forms that describe the quantity of the instances of a type, where the precise cardinality of the set is not specified. Quantifiers include vague numerals, amount terms, proportional quantifiers, and distributive quantifiers. (Section 4.1.3)