The English name Gorebyss comes from gore and byss. Gore means 'to stab' and also 'blood' which refers to this Pokémon's behaviour in sucking the blood from its foes. Byss refers to the fibres which hold bivalve marine creatures to walls which is probably a reference to Gorebyss' pre-evolution Clamperl. 'Gorebyss' could possibly be a play on the English 'gorgeous' meaning 'beautiful'.
The Japanese name 'Sakurabyss' is from the Japanese sakura meaning 'cherry blossom' and the English byss refering to molluscs. Similar to the French name from 'rosa', 'sakura' could refer to the beauty of this Pokémon or the colour of the blood that it sucks from its foes.