There are 12 words that start with 'semif'.
| semifit | semifinal | 
| semifluid | semifeudal | 
| semifinals | semifitted | 
| semifluids | semiformal | 
| semifinalist | semifinished | 
| semiflexible | semifinalists | 
Note: These 12 words that start with 'semif' are found from the USA & Canada version of the tournament Scrabble word list.