Synonyms for Once more:

adj.

afresh (adjective)
again, over, over again, once again.

adv.

anew (adverb)
another time.

adv

anew (adverb)
another time.

n.

again (noun)
another time, over.
once more (noun)
again, over again, once again.

Other synonyms:

again
over, again.
Other relevant words:
again, another time, over.