Entries related to outcrop
in Old English a common prefix with nouns, adjectives, adverbs, and verbs, "out, outward, outer; forth, away," from out (adv.). The use was even more common in Middle English, and also with the senses "outer, outside, on the outside, from without, external, externally; apart; greatly, extremely; completely, thoroughly, to completion." Other senses of out that extended into the use as a prefix include "beyond the surface or limits; to the utmost degree; to an explicit resolution."
In composition out has either its ordinary adverbial sense, as in outcast, outcome, outlook, etc., or a prepositional force, as in outdoors, or forms transitive verbs denoting a going beyond or surpassing of the object of the verb, in doing the act expressed by the word to which it is prefixed, as in outrun, outshine, outvenom, etc. In the last use especially out may be used with almost any noun or verb. [Century Dictionary]
Old English cropp "head or top of a sprout or herb, any part of a medicinal plant except the root," also "bird's craw" (the common notion is "protuberance"), cognate with Old High German kropf, Old Norse kroppr.
"The word has a remarkable variety of special senses ..." [Century Dictionary]. OED writes that "OE. had only sense 1. 'craw of a bird' and 3. 'rounded head or top of a herb'; the latter is found also in High German dialects (Grimm, Kropf, 4c); the further developments of 'head or top' generally, and of 'produce of the field, etc.' appear to be exclusively English."
Meaning "grain and other cultivated plants grown and harvested" (especially "the grain yield of one year") is from early 14c. (in Anglo-Latin from early 13c.). Probably this sense development is via the verbal meaning "cut off the top of a plant" (c. 1200).
From the notion of "top" comes the sense "upper part of a whip," hence "handle of a whip" (1560s), hence "a kind of whip used by horsemen in the hunting field" (1857). "It is useful in opening gates, and differs from the common whip in the absence of a lash" [Century Dictionary].
General sense of "anything gathered when ready or in season" is from 1570s. Meaning "a thick, short head of hair" is from 1795. Meaning "top or highest part of anything" is from late 14c. In Middle English crop and rote "the whole plant, crop and root," was figurative of totality or perfection. Crop-circle is attested by 1974.
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Big boulders outcropped