Entries linking to inshore
a Middle English merger of Old English in (prep.) "in, into, upon, on, at, among; about, during;" and Old English inne (adv.) "within, inside," from Proto-Germanic *in (source also of Old Frisian, Dutch, German, Gothic in, Old Norse i), from PIE root *en "in." The simpler form took on both senses in Middle English.
Sense distinction between in and on is from later Middle English, and nuances in use of in and at still distinguish British and American English (in school/at school). Sometimes in Middle English shortened to i.
The noun sense of "influence, access (to power or authorities)," as in have an in with, is first recorded 1929 in American English. to be in for it "certain to meet with something unpleasant" is from 1690s. To be in with "on friendly terms with" is from 1670s. Ins and outs "intricacies, complications of an action or course" is from 1660s. In-and-out (n.) "copulation" is attested from 1610s.
According to etymologists originally with a sense of "division" between land and water. But if the word began on the North Sea coast of the continent, it might as well have meant originally "land 'cut off' from the mainland by tidal marshes" (compare Old Norse skerg "an isolated rock in the sea," related to sker "to cut, shear"). Old English words for "coast, shore" were strand (n.), waroþ, ofer. Few Indo-European languages have such a single comprehensive word for "land bordering water" (Homer uses one word for sandy beaches, another for rocky headlands). General application to "country near a seacoast" is attested from 1610s.
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an inshore breeze
we swam two miles inshore