Singular and Plural Forms

singular plural forms

Rules to form singular and plural forms

To form the plural form of a medical term, you will have to learn some pluralizing rules.

You will add –s to words ending in vowels or consonant except, s, x, z, or y. You will add –es to words ending in s, x, or z. You will add –ies to words in –y (remove the y) preceded by a consonant. When the word ends  in –y preceded by a vowel, you will use –s.

Example: reflex will become reflexes

You will add –e to Latin terms ending in –a. You will add-i to Latin words ending in –us(remove the-us)

Example: fossa will become fossae

You will add –a to Greek words ending in –on(remove –on); Add –a to Latin words ending in –um(remove –um)

Example: ganglion will become ganglia

You will change –sis to –ses in Greek words ending with -sis

Example: neurosis will become neuroses

Here is a table to help you with the rules:

Rules for Singular Plural
Words ending in a bursa bursae
Words ending in itis arthritis arthritides
Words ending in ex(or ix) appendix appendices
Words ending in on ganglion ganglia
Words ending in um ovum ova
Words ending in us alveolus alveoli
Words ending in nx phalanx phalanges
Words ending in is diagnosis diagnoses

Plural forms may seem a bit confusing. Once you learn the rules, you will be able to identify the correct spelling quickly.

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