'unsymbolic' is a Modern English formation from the negative prefix 'un-' + the adjective 'symbolic'. 'symbolic' ultimately traces back to Late Latin 'symbolicus' and Greek 'symbolikos', from 'symbolon' meaning 'token' or 'sign'.

'symbolic' came into English via Late Latin 'symbolicus' (and/or Old French), itself from Greek 'symbolikos' and 'symbolon'. The negative prefix 'un-' (Old English/West Germanic) was attached in Modern English to form 'unsymbolic'.

Originally the Greek 'symbolon' meant 'token' or 'sign', and over time 'symbolic' came to mean 'serving as a symbol' or 'representative'; 'unsymbolic' therefore means 'not serving as a symbol' or 'lacking symbolic significance'.