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Irregular Plurals in English
List of Irregular Plurals in English
The rules for forming plurals in English are complicated, and there are many irregular plurals. Here is a list of the most common irregular plurals. (These are the ones that cause the most problems for native English speakers and learners.)A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
A
- agenda (This was a plural word. It is now a singular word with the plural agendas.)
- air
- aircraft
- amoeba
- analysis
- antenna
- axis
B
C
- cactus
- calf
- cello
- census
- chief
- child
- cliff
- crisis
- criteria (This is a plural word. The singular is criterion.)
- curriculum

D
- data (This is the Latin plural of "datum." However, many treat data as a singular word nowadays.)
- deer
- diagnosis
- dice
- dictionary
- do and don't (There are several ways to write this term as a plural.)
- doe
- domino
- donkey
- dragonfly
- dwarf
- dye
E
F
G
H
I
J
K
L
M
- man
- media
- mango
- money
- mongoose
- moose
- mouse
- Mr., Mrs., Ms., and Miss (This page covers the plurals of these honorifics.)
- mummy
- music
N
O
P
Q
R
S
T
U
V
W
X
Y
- yes and no (There are several ways to write this term as a plural.)
- Yeti
Z
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