prefix
or an-
Etymology: Medieval Latin, from Latin ana- & Late Latin an-, from Greek ana-, an-, from ana up, on — more at on
1. : up : upward
an ode
Ana cardium
2. : back : backward
ana nym
3. : again : anew
ana genesis
4. usually ana- , chemistry , usually italic : having substituents in positions 1 and 5 in two fused 6-membered rings (as in naphthalene, quinoline)