The word is unique to this attestation, and is not found in other dictionaries. It is, however, a straightforward adverbial construction of the adjective noveler2.
adv.
1with a fondness for novelty:
(
c.1136-65; MS: c.1200
)
Ki molx e vains est e legier En bone ovraigne comencer, Novelerement la comence E tost s'en part par negligence
10829
novelerement (c.1136-65)