'halotolerant' originates from a modern scientific compound combining the Greek prefix 'halo-' (from Greek 'hals', meaning 'salt, sea') and the adjective 'tolerant' (from Latin 'tolerare', 'to bear').

'tolerant' passed from Latin 'tolerare' into Medieval/Old French as 'tolerant' and then into Middle English as 'tolerant'; the prefix 'halo-' entered scientific English via New Latin from Greek 'hals'. The compound 'halotolerant' is a 20th-century scientific formation.

Initially the elements meant 'salt' + 'able to bear', and the compound has retained this literal meaning as 'able to tolerate salt' in modern scientific usage.