I. Nouns ending in ‘is’:
Singular Nouns that end in ‘is’ form their plural adding ‘es’ and eliminating ‘is’.
Singular
axis
basis
crisis
diagnosis
hypothesis
oasis
synopsis
thesis
Plural
axes
bases
crises
diagnoses
hypotheses
oases
synopses
theses
Meaning
affiliation, an imaginary line
source, origin
disaster, calamity
opinion, analysis
theory , assumption
Haven, refuge, green land in a desert
Outline, abstract
Theory, proposal, opinion
II. Nouns ending in ‘us’:
Singular nouns ending in ‘us’ form their plural adding ‘i’ eliminating ‘us’.
Singular
Abacus
Plural
abaci
Alumnus
alumni
bacillus
Locus
stimulus
bacilli
loci
stimuli
Meaning
a frame with beads in a string used for
counting
a past student(boy) of an educational
institution
a micro organism , a germ
a particular, place, point or position
incentive, a motivating factor, a spur
III. Nouns ending in ‘x’:
Singular nouns ending in ‘x’ form their plural adding ‘ices’ eliminating ‘x’.
Singular
Index
Plural
indices
Matrix
matrices
Appendix
appendices,
appendixes
Apex
Apices, apexes
Meaning
directory, catalogue, guide, an
alphabetical list
mould, atmosphere, a mass of rock,
maths
a section of additional information at
the end of a book, lower end of the
large intestine
highest point
IV. Nouns ending in ‘um’:
Singular nouns ending in ‘um’ form their plural adding ‘a’ eliminating ‘um’.
Singular
Addendum
Bacterium
Corrigendum
Datum
Dictum
erratum
forum
ovum
stratum
Plural
addenda
Bacteria
corrigenda
Data
Dicta
Errata
Fora
Ova
strata
Meaning
addition, appendix
micro organism
error to be corrected
collection of facts
accepted opinion
mistakes found in the manuscript
Formal group
a mature female reproductive cell
division, layer
V. Nouns ending in ‘um’:
Some singulars ending in ‘um’ have two forms of plurals.
Singular
Acquarium
Plural
acquaria
Curriculum
Medium
Random
Stadium
Symposium
ultimatum
curricula or curriculums
media
randa or randoms
stadia or stadiums
symposia or symposiums
Ultimata or ultimatums
Meaning
A container to keep water
creatures and plants
syllabus, course
means of communication
chance, accidental
sports ground
conference, seminar
A final warning
VI. Nouns ending in ‘us’:
Some singulars ending in ‘us’ have two plural forms.
Singular
cactus
focus
fungus
genius
nucleus
radius
Plural
cactuses or cacti
focuses, foci
funguses or fugui
geniuses or genii
nucleuses or nuclei
Radiuses or radii
stylus
syllabus
terminus
Styluses or styli
syllabuses or syllabi
terminuses or termini
Meaning
desert plant
centre, focal point
mildew, mould
intellectual, scholar
minute cell, core of a cell
a specified distance from a
centre in all direction
A pen drive, print type
programme of study
last stop, station, end
VII. Nouns ending in ‘a’:
Some nouns ending in ‘a’ have two plural forms.
Singular
Alumna
Amoeba
Antenna
Formula
Nebula
Vertebra
Plural
alumnae or alumnas
amoebae or amoebas
antennae or antennas
formulae or formulas
nebulae or nebulas
vertebrae or vertebras
Meaning
a living cell
aerial, feeler
method, principle, rule
a cloud of gas
Back bone
VIII. Nouns ending in ‘eau’:
Some nouns ending in ‘eau’ have two plural forms.
Singular
bureau
plateau
tableau
Plural
bureaux or bureaus
plateaux or plateaus
tableaux or tableaus
Meaning
an official group
a table land
motionless figures
representing a scene,
IX. Irregular plural forms:
Singular
Foot
Goose
Louse
Man
Mouse
Tooth
Woman
Plural
Feet
Geese
Lice
Men
Mice
Teeth
Women
X. Plurals of compound nouns:
Singular
Father - in – law
Board of education
Attorney general
Court-martial
Man servant
Woman doctor
Forget-me-not
Tooth brush
Step son
Passer – by
Plural
Fathers - in – law
Boards of education
Attorney generals or
attorneys general
Courts-martial
Men servants
Women doctors
Forget-me-nots
Tooth brushes
Step sons
Passers – by