There are 9 12-letter words that start with 'coa'.
| coacervation | coadaptation | coadjutrices | 
| coagulations | coalescences | coalitionist | 
| coarctations | coarsenesses | coauthorship | 
Note: These 9 12-letter words that start with 'coa' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with coal, coas, coat, coac, coag, coad, coar, coap, coax, coan, coau, coae, coam.
4-letter words start with 'coa' (3)