There are 15 12-letter words that start with 'exo'.
| exobiologies | exobiologist | exonerations |
| exonucleases | exopeptidase | exophthalmic |
| exophthalmos | exophthalmus | exorbitances |
| exorbitantly | exorcistical | exoskeletons |
| exoterically | exothermally | exoticnesses |
Note: These 15 12-letter words that start with 'exo' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with exot, exor, exon, exos, exoc, exod, exog, exop, exob, exoe.
4-letter words start with 'exo' (1)