a) A member of a class of words functioning in a noun phrase to identify or distinguish a referent without describing or modifying it. Examples of determiners include articles (a, the), demonstratives (this, those), cardinal numbers (three, fifty), and indefinite numerals (most, any, each).
The "steel-yards" and "measures" were the only determiners of weight and quantity — as the hour-glass and sun dial were of time — possessed at first (so far as appears) by the passengers of the Pilgrim ship,
b) A dependent function in a noun phrase marking the NP as definite or indefinite. This function is usually filled by words in the determinative class but may be filled by other elements such as a genitive pronoun.
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