'hemoconcentration' originates from the combining form 'hemo-' (from Greek 'haima', meaning 'blood') and the English noun 'concentration' (from Latin 'concentratio' via Old/Middle French), where 'hemo-' meant 'blood' and 'concentration' meant 'the act of bringing together or making dense'.

'hemo-' comes from Greek 'haima' and entered scientific/medical English as a combining form in New Latin; 'concentration' derives from Latin 'concentratio' through Old/Middle French into English. The modern compound 'hemoconcentration' arose in medical English by joining these elements to describe increased density of blood components.

Originally the parts meant 'blood' and 'the act of concentrating'; over time the compound came to denote specifically 'an increase in the concentration of cellular elements in blood (typically from plasma loss)'.