This sole attestation produces a unique adverbial form of resemblant, the present participle of resembler1 used as an adjective.
adv.
1similarly, likewise:
(
1300; MS: s.xiv1
)
Ses armes ne furent par (l. pas) soules D’esiente (l. De sieute?) en le apparellement Kar teles ot resemblantment Johans de Langcastre
103.78
resemblantment (1300)