Other hyponyms of letter of the alphabet include
descender,
digram,
digraph,
initial,
A,
a,
B,
b,
C,
c,
D,
d,
E,
e,
F,
f,
G,
g,
H,
h,
I,
i,
J,
j,
K,
k,
L,
l,
M,
m,
N,
n,
O,
o,
P,
p,
Q,
q,
R,
r,
S,
s,
T,
t,
U,
u,
V,
v,
double-u,
W,
w,
ex,
X,
x,
wye,
Y,
y,
ezed,
izzard,
Z,
z,
zed,
zee,
alpha,
beta,
gamma,
delta,
epsilon,
zeta,
eta,
theta,
iota,
kappa,
lambda,
mu,
nu,
xi,
omicron,
pi,
rho,
sigma,
tau,
upsilon,
phi,
chi,
khi,
psi,
omega,
aleph,
beth,
gimel,
daleth,
he,
waw,
zayin,
heth,
teth,
yodh,
kaph,
lamedh,
mem,
nun,
samekh,
ayin,
pe,
sadhe,
qoph,
resh,
sin,
shin,
taw,
polyphone,
polyphonic letter,
block capital,
block letter,
vowel,
consonant,
yus.