There are 13 13-letter words that start with 'obs'.
| obscurantisms | obscurantists |
| obscurenesses | observability |
| observational | observatories |
| obsessionally | obsessiveness |
| obsolescences | obsolescently |
| obstetrically | obstetricians |
| obstinateness | |
Note: These 13 13-letter words that start with 'obs' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with obse, obst, obsc, obso, obsi.
6-letter words start with 'obs' (1)