| Groundbreaking person |
| Groundbreaking old Fords |
| Groundbreaking items? |
| With "The," groundbreaking Showtime TV series |
| Card manufacturer? (or heart device missing a piece) |
| Groundbreaking development? |
| Groundbreaking construction tool? |
| Groundbreaking comic Lenny |
| Groundbreaking admission from Ellen in a 1997 sitcom |
| It's involved in groundbreaking events |
| Groundbreaking anime film of 1988 |
| Groundbreaking invention? |
| Groundbreaking sitcom, and a hint to four different three-letter words concealed by starred answers |
| Kirk's partner in a groundbreaking 1968 interracial kiss |
| Groundbreaking spot? |
| Groundbreaking discoveries? |
| Groundbreaking |
| Groundbreaking tool |
| Groundbreaking implement |
| It can be groundbreaking |
| Groundbreaking 1970s sitcom |
| Groundbreaking garden tool |
| It does groundbreaking work |
| It's groundbreaking |
| Does groundbreaking work? |
| Groundbreaking musical |
| Baloney manufacturer? |
| Groundbreaking 1988 anime film |
| Groundbreaking Al Jolson title role |
| Did groundbreaking work? |