There are 19 10-letter words that start with 'gi'.
Note: These 19 10-letter words that start with 'gi' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with gin, gir, gig, gib, gim, gil, gif, gid, gia, gip, giv, git, gis, gie, giz.
3-letter words start with 'gi' (7)