'autodiagrammatic' originates from Greek elements: 'auto-' from 'autos' meaning 'self' and 'diagrammatic' ultimately from Greek 'diagramma' meaning 'a drawing' or 'that which is marked', combined in English with the adjectival suffix '-ic'.

'autodiagrammatic' is a modern English coinage formed by combining 'auto-' + 'diagrammatic'. 'Diagrammatic' entered English via Latin/Medieval Latin from Greek 'diagramma'; the compound itself is a recent formation rather than an inherited single-word root.

The original elements meant 'self' and 'relating to a drawing'; as a modern compound they have come to mean 'capable of being represented by its own diagram' or 'self-diagramming'.