There are 4 14-letter words that start with 'supp'.
supplantations | supportability |
supportiveness | supposititious |
Note: These 4 14-letter words that start with 'supp' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with suppl, suppo, suppr, suppu, suppe, suppi.
6-letter words start with 'supp' (4)