Eleven letter anagrams

necessarian renaissance
calligraphy graphically
probationer reprobation
cosmetician encomiastic
considerate desecration
deification edification
peripatetic precipitate
ethological theological
incorporate procreation
offuscation suffocation
colonialist oscillation
attentively tentatively
enumeration mountaineer
importunate permutation
impressible permissible
centerpiece centrepiece
conditioner recondition
description discerption
reconnoiter reconnoitre
interpreter reinterpret

Found, spring 2000, in dictionary by dpd using process described here.