Word
alter
Phoneticsal·ter, stress on the first syllable
US/ˈɔɫtɝ/
UK/ˈɒltɐ/
Definitions
01to change something
B2 · Upper Intermediate Academic
v. to change something slightly, often to make it better or more suitable.
v. to make a structural or formal change to something without replacing it entirely.
日本語:変える※
“We had to alter our travel plans because the flight was cancelled.”
“The researchers were forced to alter their hypothesis after the initial data revealed a significant correlation they had not previously considered.”
Usage
Often used with a direct object; can also be used without an object to mean 'to become different'.
Pitfall
He went to the church to pray at the alter.
He went to the church to pray at the altar.
Do not confuse 'alter' (to change) with 'altar' (a table used in religious ceremonies).
02to tailor clothes
B2 · Upper Intermediate
v. to change a piece of clothing so that it fits you better.
v. to adjust the dimensions of a garment for a better fit.
“The trousers were too long, so I took them to a tailor to have them altered.”
“She decided to alter the vintage dress herself, narrowing the waist and shortening the hem to create a more contemporary silhouette.”
03to neuter an animal
C1 · Advanced Medicine American English
v. to perform a medical operation on an animal so it cannot have babies.
v. to castrate, neuter, or spay a domestic animal.
“The animal shelter requires all owners to alter their pets before adoption.”
“Veterinarians generally recommend that owners alter their dogs at a young age to prevent unwanted litters and certain health complications.”
04an alternate personality
C2 · Proficiency Countable noun Psychology Technical
n. one of several different personalities that a person might have in some mental health conditions.
n. a distinct personality state or identity within an individual, typically associated with dissociative identity disorder.
“The patient described how an alter would sometimes take control during stressful moments.”
“Clinical observation focused on the transition between the primary identity and a protective alter during the therapeutic session.”
Usage
Used as a countable noun in clinical psychology.
Synonyms
Collocations
Common phrases and expressions where native English speakers use the word “alter” in context.
Verb
01. alter balance
“Adding more weight to one side will alter the balance of the scale.”
verb + noun
02. alter behaviour
“The study looks at how social media can alter human behaviour over time.”
verb + noun
03. alter course
“The pilot had to alter course to avoid the approaching storm.”
verb + noun
04. alter nature
“Human intervention can permanently alter the nature of an ecosystem.”
verb + noun
05. alter pattern
“Changing your sleep schedule can alter your natural sleep pattern.”
verb + noun
06. alter relationship
“The disagreement did not alter their relationship as business partners.”
verb + noun
07. alter structure
“The architect decided to alter the structure of the roof to allow more light.”
verb + noun
Adverb
08. significantly alter
“The new evidence could significantly alter the outcome of the trial.”
adv + verb
09. slightly alter
“We had to slightly alter our travel plans due to the bad weather.”
adv + verb
10. substantially alter
“The renovation will substantially alter the layout of the ground floor.”
adv + verb
Real-World Examples
“This can alter natural flow patterns and reduce the amount of water in rivers.” “And readers can alter their votes after reacting to comments.” “It also lists whether AI was used to alter the image.” Etymology
From Old French alterer (French altérer), from Medieval Latin alterāre (“to make other”), from Latin alter (“the other”), from al- (seen in alius (“other”), alienus (“of another”), etc.; see alias, alien, etc.) + compar. suffix -ter.
Probably from alter ego.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Word family
VERB
NOUN
Domain
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.B2 FirstIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.5.5–6.5TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 4.0–4.572–94TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.785–944
- Frequency
- Common
- Level
- B2 · Upper IntermediateOxford
- Updated
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QR code
englishreference.com/q/alter
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「日本語」 data: JMdict (EDRDG), CC BY-SA 4.0