'omitter' originates from Latin, specifically the word 'omittere', where 'ob-' meant 'away' and 'mittere' meant 'to send.'

'omitter' developed from the verb 'omit' (from Latin 'omittere') which entered English via Late Latin/Old French forms; the agentive English suffix '-er' was later added to form the noun 'omitter.'

Initially, the Latin root referred to 'to send away, let go,' but over time the sense shifted in English to 'to leave out or neglect,' which is reflected in 'omitter' as 'one who leaves something out.'