There are 18 9-letter words that start with 'deca'.
| decadence | decadency | decadents |
| decagonal | decagrams | decahedra |
| decalcify | decaliter | decalogue |
| decameter | decamping | decanters |
| decanting | decapodal | decapodan |
| decathlon | decayable | decayless |
Note: These 18 9-letter words that start with 'deca' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with decar, decal, decap, decam, decan, decad, decay, decag, decas, decat, decaf, decah.
5-letter words start with 'deca' (3)