'onshore' originates from the combination of 'on' and 'shore', where 'on' meant 'in contact with' and 'shore' referred to 'the land along the edge of a sea, lake, or other large body of water'.

'onshore' has remained relatively unchanged in its form and meaning since its inception in English.

Initially, it meant 'towards the shore', and this meaning has largely remained the same in modern usage.