haycock vs haystack

haycock and haystack both are nouns.

Word	Noun	Adjective	Verb	Adverb
haycock	Yes	No	No	No
haystack	Yes	No	No	No

As nouns, haystack is a hypernym of haycock; that is, haystack is a word with a broader meaning than haycock:

haycock: a small cone-shaped pile of hay that has been left in the field until it is dry enough to carry to the hayrick
haystack: a stack of hay

Other hypernyms of haycock include hayrick, rick.

haycock (noun)	haystack (noun)
a small cone-shaped pile of hay that has been left in the field until it is dry enough to carry to the hayrick	a stack of hay