There are 6 12-letter words that start with 'allo'.
| alloantibody | alloantigens | allografting |
| allomorphism | allopurinols | allosauruses |
Note: These 6 12-letter words that start with 'allo' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with allot, allop, alloc, allog, allow, allom, allos, allod, alloa, allon, alloy, allob, allov, allox.
5-letter words start with 'allo' (4)