From Longman Dictionary of Contemporary Englishonshoreon‧shore /ˌɒnˈʃɔː◂ $ ˌɑːnˈʃɔːr◂, ˌɒːn-/ adjective [only before noun], adverb 1 DNSGon the land, not in the sea → offshore, inshore onshore oil production2 DNHEMonshore winds are moving from the sea towards the land → offshore
Examples from the Corpus
onshore• onshore oil reserves• strong onshore windsFrom Longman Business Dictionaryonshoreon‧shore /ˌɒnˈʃɔː◂ˌɑːnˈʃɔːr◂, ˌɒːn-/ adjective1involving an activity performed in a particular country, rather than outside itThe Thai baht reached new lows in onshore trading in Bangkok.2onshore bank/company/investment etcTAX a bank etc that is based in a country where taxes are at normal levels, laws are strict etcThe bank now wants to expand in onshore business centres such as London, New York and Tokyo.3connected with oil and gas production that is done on landThere was only one onshore discovery last year out of seven exploration wells drilled. —onshore adverbSome of these deals are much more generous than comparable products onshore. 