Word Formation: Prefix, Suffix, Noun-Adjective-Verb Forms and Methods of Word-Building
This page gives all the major ways to build new words in English — prefix, suffix, compounding, conversion, clipping, blending, acronym and back-formation — along with a useful list of noun, verb, adjective and adverb forms.
- Class 6-10 grammar level
- 7 min read
What is Word Formation
Word formation is the process by which a new word is built from an existing word or word-part. The core part of a word to which a prefix or suffix attaches is called the root or base word — for example, in 'unhappiness', 'happy' is the base word, 'un-' is the prefix and '-ness' is the suffix.
Remember the most important distinction: a prefix attaches at the start of a word and usually changes only the meaning, not the word class — happy (adj) → unhappy (adj). A suffix attaches at the end of a word and usually does change the word class — happy (adj) → happiness (noun), danger (noun) → dangerous (adj), discover (verb) → discovery (noun). This is exactly why questions like 'noun form', 'adjective form' in competitive exams are based on suffixes. Some prefixes also change the word class, such as en-: danger (noun) → endanger (verb), able (adj) → enable (verb).
Major Prefixes
| Prefix | Meaning | Example |
|---|---|---|
| un-, in-, dis-, non- | not / opposite | unhappy, incorrect, dishonest, non-violent |
| im- (before p, b, m) | not | impossible, imbalance, immature |
| il- (before l), ir- (before r) | not | illegal, illiterate, irregular, irresponsible |
| mis- | wrongly | misuse, misunderstand, mislead |
| re- | again | rewrite, rebuild, reopen |
| pre-, post- | before / after | prehistoric, preview, postwar |
| over-, under- | too much / too little | overload, underestimate |
| sub-, inter-, trans- | under / between / across | subway, international, transport |
| co-, anti- | together / against | co-operate, antibiotic |
| en- | to make/cause (forms a verb) | enrich, enlarge, endanger |
Identifying Word Class by Suffix
| Form produced | Main suffixes | Example |
|---|---|---|
| Noun | -tion/-sion, -ment, -ness, -ity, -ance/-ence, -y, -dom, -hood, -ship, -er/-or | cultivation, erosion, movement, kindness, ability, importance, discovery, freedom, childhood, friendship, teacher |
| Adjective | -ous, -ful, -less, -able/-ible, -al, -ive, -y, -ish, -ic | dangerous, useful, careless, readable, intentional, active, windy, childish, poetic |
| Verb | -ise/-ize, -en, -ify, -ate | modernise, widen, beautify, activate |
| Adverb | -ly, -wards, -wise | intentionally, backwards, clockwise |
Caution: -ly doesn't always form an adverb — friendly, lovely, lonely are adjectives. So also check how the word is actually used.
Noun-Verb-Adjective-Adverb Forms (Exam-Useful List)
| Noun | Verb | Adjective | Adverb |
|---|---|---|---|
| discovery | discover | discoverable | — |
| intention | intend | intentional | intentionally |
| danger | endanger | dangerous | dangerously |
| cultivation | cultivate | cultivated / cultivable | — |
| erosion | erode | erosive | — |
| decision | decide | decisive | decisively |
| beauty | beautify | beautiful | beautifully |
| strength | strengthen | strong | strongly |
| width | widen | wide | widely |
| success | succeed | successful | successfully |
| knowledge | know | knowledgeable | knowledgeably |
| courage | encourage | courageous | courageously |
| ability | enable | able | ably |
| continuity | continue | continuous | continuously |
'—' means there is no commonly used form for that word class.
Other Methods of Word Formation
| Process | Meaning | Example |
|---|---|---|
| Compounding | Joining two independent words | blackboard, sunflower, toothbrush, classroom, mother-in-law |
| Conversion | Changing a word's class without altering its form | a walk (noun) → to walk (verb); an email → to email |
| Clipping | Shortening a long word | examination → exam, telephone → phone, laboratory → lab |
| Blending | Combining parts of two words | smoke + fog → smog, breakfast + lunch → brunch, motor + hotel → motel |
| Acronym | A word formed from the first letters of other words, pronounced as a word | NASA, UNESCO, radar (radio detection and ranging) |
| Back-formation | Removing a suffix from an established longer word to form a shorter one | editor → edit, television → televise |
Spelling Rules When Adding a Suffix
(1) A word's final silent e is usually dropped before a suffix beginning with a vowel — cultivate → cultivation, erode → erosion (here the 'd' also changes to 's'), decide → decision; but it is usually kept before a suffix beginning with a consonant — hope → hopeful, move → movement. There are some exceptions: argue → argument, true → truly.
(2) In a word ending in consonant + y, the y is changed to i — happy → happiness, beauty → beautiful; but it doesn't change in vowel + y — enjoy → enjoyment. (3) In a short word ending in one vowel + one consonant, the consonant is doubled — begin → beginning, run → runner. (4) When forming an adverb from an adjective ending in -al or -ful, -ly is added, so you get a double 'll' — intentional → intentionally, careful → carefully; 'intentionaly' is a misspelling.
Memory Trick / Exam Tip
Before choosing an answer, look at the word used in the question — if it asks for the 'noun form', pick the option with -tion, -ment, -ness, -ity or -y; if it asks for 'adjective', pick the one with -ous, -ful, -al, -ive or -able; -ly is usually an adverb. If asked for the base word, remove the suffix and put the silent e back: cultivation → cultivate, erosion → erode.
Frequently Asked Questions
What is the difference between a Prefix and a Suffix?+
A prefix attaches at the start of a word and usually changes the meaning (happy → unhappy), while a suffix attaches at the end and usually changes the word class (happy → happiness).
What is the noun form of 'Discover'?+
The noun form of 'discover' is 'discovery'. 'Invention' is the noun of the verb 'invent', not of 'discover'.
What is a base word or root word?+
The core part of a word to which a prefix/suffix attaches — for example, the base word of 'erosion' is 'erode' and of 'cultivation' is 'cultivate'.