There are 21 7-letter words that start with 'sig'.
| siganid | sighers | sighing | sighted | 
| sighter | sightly | sigmate | sigmoid | 
| signage | signals | signees | signers | 
| signets | signify | signing | signior | 
| signora | signore | signori | signors | 
| signory | |||
Note: These 21 7-letter words that start with 'sig' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with sign, sigh, sigm, sigl, siga, sigi.
4-letter words start with 'sig' (2)