There are 11 words that start with 'lumpi'.
| lumpier | lumpily | 
| lumping | lumpish | 
| lumpiest | lumpiness | 
| lumpingly | lumpishly | 
| lumpinesses | lumpishness | 
| lumpishnesses | |
Note: These 11 words that start with 'lumpi' are found from the USA & Canada version of the tournament Scrabble word list.