'inclinometer' originates from English formations combining 'incline' + '-meter', where 'incline' ultimately comes from Latin 'inclinare' meaning 'to bend or lean' and '-meter' comes from Greek 'metron' meaning 'measure'.

'incline' came into English from Latin 'inclinare' (via Old French/Medieval Latin influences) and names of measuring instruments were formed in Modern English by adding the Greek-derived suffix '-meter'; these elements combined in the 19th–20th century to produce 'inclinometer'.

Initially the roots referred to 'leaning' ('inclinare') and 'measure' ('metron'); combined as 'inclinometer' the meaning has been a specialized instrument name for measuring inclination, a sense that has remained consistent since its formation.