There are 10 12-letter words that end with 'onic'.
| amphictyonic | anticyclonic | dodecaphonic |
| electrotonic | philharmonic | quadraphonic |
| quadriphonic | stereophonic | technetronic |
| zwitterionic | ||
Note: These 10 12-letter words that end with 'onic' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words end with tonic, ronic, honic, ionic, monic, sonic, gonic, yonic, conic, lonic, donic, eonic, bonic, aonic, konic, ponic, xonic, zonic, fonic, nonic, uonic, vonic.
5-letter words end with 'onic' (5)