There are 18 words that start with 'subf'.
| subfix | subfile | subfusc |
| subfield | subfiles | subfixes |
| subfloor | subfluid | subframe |
| subfuscs | subfamily | subfields |
| subfloors | subfossil | subframes |
| subfossils | subfamilies | subfreezing |
Note: These 18 words that start with 'subf' are found from the USA & Canada version of the tournament Scrabble word list.