'auxanometer' originates from Greek elements via modern scientific formation: Greek 'auxan-' (from 'auxanein'/'auxanos') meaning 'increase, growth' combined with Greek 'metron' meaning 'measure' (through New Latin/modern coinage).

'auxanometer' was formed in scientific English by combining the Greek-derived prefix 'auxano-' (used in New Latin/modern scientific terminology) with the suffix '-meter' (from Greek 'metron'); this produced the modern English technical term 'auxanometer'.

Initially it meant an instrument for measuring increase or growth in a general sense; it has remained specialized to mean an instrument for measuring biological (especially plant) growth.