A is for the Aldebaron Colony, Elizabeth Dehner's posting before joining the Enterprise crew in 2265.
B is for Breen Confederacy.
C is for Cardassian Union.
D is for Denobulan face sac.
E is for Exeter. Enterprise's sister that was infected with a very nasty bacteria that killed the crew.
F is for Farragut, USS
G is for Gul Dukat
H is for Horta
I is for Illicit trade in biomimetic gel. A major offense under late 24th century Federation law.
J is for Jews in Space. i.e. William Shatner and Leonard Nimoy.
K is for Klingon B'rel-class Bird of Prey.
L is for Lesbian snogging in the mirror universe.
M is for Merrikus, a human Starfleet Academy dropout who later went on to become a citizen of power and high status on a world ruled by a Roman-like culture.
N is for NASA. National Aeronautics and Space Administration.
O is for Operation Retrieve, conceived in early 2293 as a proposal to rescue Kirk and McCoy from Klingon captivity.
P is for Picard.
Q is for Quark's Bar. Come for the drinks. Stay for the holosuites.
R is for Riker. He leans a lot.
S is for Stol. Quark's cousin. Ishka liked to write letters to him.
T is for T'Pol's bum.
U is for USS, the prefix used in the name of almost every starship ever launched and operated by the Federation Starfleet.
V is for Vaal. A victim of Kirk's god-slaying proclivities.
W is for Wobble. The Enterprise tended to do this when struck by enemy fire or space debris.
X is for Xindi Death Star.
Y is for Yridian head wrinkles.