'mainland' originates from Old English, specifically from the elements 'mægen' (as the root for 'main') where 'mægen' meant 'strength, power' and 'land' where 'land' meant 'land'. 'raise' (past participle 'raised') originates from Old Norse, specifically the word 'reisa', where 'reisa' meant 'to raise or lift'.

'mainland' developed in Middle and Modern English from the combination of 'main' (principal) + 'land' and came to mean the principal landmass. 'raise' developed from Old Norse 'reisa' through Middle English forms and its past participle 'raised' came to be used adjectivally (e.g., 'city-raised', 'farm-raised'). 'mainland-raised' is a modern English compound adjective combining these elements to indicate upbringing on the mainland.

Initially, 'raise' primarily meant 'to lift up' physically; over time it broadened to include 'to rear or bring up (a person or animal)'. Consequently, the compound 'mainland-raised' came to mean 'brought up on the mainland' rather than anything about physical lifting.