A is for All You Need is Love, a song probably performed by Stamets' uncle's Beatles tribute band.
B is for Bondgroupes. On Andor they are necessary for reproduction.
C is for Ceti Alpha V, where Kirk marooned KHAAAAAAAAAAAAAAAAAAAAAAAAN!!!
D is for Data's crazy brother Lore, he was demented and ended dismantled...
E is for an Electromagnetic Pulse initiated by the Red Angel that changed the course of life on Kaminar...
F is for Faux Bashir, Bashir is replaced by a changeling at least three times and is possessed by a criminal once, that I remember of.
G is for Gegis, a Ferengi privateer who helped DaiMon Nunk try to "steal" Seven of Nine for her nanoprobes.
H is for the Homing beacon that messed up Seven so much she grew new implants on her face!
I is for Illusions created by the Talosians. Only ever appeared in TOS, and most likely never to be seen again.
J is for Jonathan Archer, He's Not like a gazelle, or so he says.
K is for Kosinski, a propulsion specialist who turned out to be less than stellar.
L is for Lela Dax.
M is for Mister Spock.
N is for Nhan, Chief of Security of the USS Discovery.
O is for Ornery Ornarans.
P is for the Prime Directive, Picard sat on it in Nemesis.
Q is for the Qualor II surplus depot.
R is for Rogue Planets, they're sometimes inhabited by changelings.
S is for Sex. Q are above Sex.
T is for T'Pring, who was cold and calculating even for a Vulcan.
U is for Ursa Minor, The constellation of Polaris, Aka the North Star, an episode of ENT.
V is for Vok, a Klingon.