There are 11 13-letter words that start with 'ser'.
| serendipities | serendipitous |
| serialization | sericulturist |
| seriousnesses | serodiagnoses |
| serodiagnosis | serologically |
| serpiginously | serriednesses |
| servilenesses | |
Note: These 11 13-letter words that start with 'ser' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with seri, serv, sero, sere, serr, sera, serg, serm, serp, serf, serj, seru, serd, sers.
4-letter words start with 'ser' (4)