There are 16 words that start with 'loop'.
| loop | loops | loopy | 
| looped | looper | loopers | 
| loopier | loopily | looping | 
| loophole | loopiest | loopholed | 
| loopholes | loopiness | loopholing | 
| loopinesses | ||
Note: These 16 words that start with 'loop' are found from the USA & Canada version of the tournament Scrabble word list.