There are 91 12-letter words that start with 'super'.
Note: These 91 12-letter words that start with 'super' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with supers, superc, supera, superp, superi, superh, superf, supere, superm, supern, superl, superb, superv, superg, supero, supert, superr, superw, superj, superd, superq.
6-letter words start with 'super' (2)