“Authorize” and “authorise” are regional spelling variants of the same verb. Dictionary guidance recognizes both, with “authorise” associated especially with British usage, so consistency with the intended regional or house style is the key choice.
ReviewedEvidence1 sourceSectionEnglish Usage
Quick answer
Both are established spellings of the same verb; choose “authorize” or “authorise” according to your regional or house style and stay consistent.
Key details
Confusion Familyregional-variant
Rule Familyregional-spelling
Termsauthorize, authorise
Further guidance
Core difference
The two spellings share the same core meaning and differ by regional/style convention rather than by grammatical function.
Usage Boundary
Do not label one spelling universally correct and the other universally wrong; follow the audience or publication style.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
“Apologize” and “apologise” are regional spelling variants of the same verb. Cambridge marks “apologise” as the usual UK form, so the practical choice is to follow the regional or house style required by the audience.
“Capitalize” and “capitalise” are regional spelling variants of the same verb. Cambridge records the British “capitalise” variant, so writers should choose the form that matches their regional or publication style and use it consistently.
“Realize” and “realise” are regional spelling variants of the same verb. Cambridge notes the UK “realise” form; which spelling to publish depends on the regional or house style being followed, not on a difference in meaning.
“Specter” and “spectre” are regional spellings of the same noun rather than words with different meanings. Cambridge identifies specter as the US spelling of spectre, so consistency with regional style is the main choice.
