There are 3 13-letter words that start with 'tac'.
| tachistoscope | taciturnities |
| tactfulnesses | |
Note: These 3 13-letter words that start with 'tac' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with tack, tach, tact, taci, taco, tace, taca, tacn, tacr.
4-letter words start with 'tac' (5)