APA capitalizes “Against” internally because it has at least four letters. Chicago 18 also capitalizes it because prepositions of five letters or more are capitalized. MLA ordinarily lowercases internal prepositions, while any principal-word use needs grammatical classification before an automated decision.
ReviewedEvidence6 sourcesSectionWriting & Style
Quick answer
APA: capitalize. Chicago 18: capitalize. MLA: lowercase when “against” is a preposition; any non-prepositional principal-word use must be classified before automation. First/last-word rules can override ordinary internal treatment.
Key details
APA 7Capitalize internally because it has seven letters.
Automation NoteUse phrase structure and grammatical role before applying MLA automatically. Preserve first/last-word and subtitle-boundary overrides.
Chicago 18Capitalize internally; Chicago 18 capitalizes prepositions of five letters or more.
MLA 9Lowercase internally when it functions as a preposition.
TermAgainst
Word Classpreposition
Style-by-style guidance
APA 7
Capitalize internally because it has seven letters.
Chicago 18
Capitalize internally; Chicago 18 capitalizes prepositions of five letters or more.
MLA 9
Lowercase internally when it functions as a preposition.
Important caveats
Automation boundary
APA and current Chicago are deterministic for this reviewed spelling in ordinary internal position. MLA remains role-sensitive where the word can function outside a prepositional role; boundary rules still override internal rules.
Further guidance
Quick rule
APA: capitalize. Chicago 18: capitalize. MLA: lowercase when “against” is a preposition; any non-prepositional principal-word use must be classified before automation. First/last-word rules can override ordinary internal treatment.
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.
Prepositions are one of the clearest places where title styles diverge. APA uses a four-letter major-word threshold, Chicago 18 capitalizes prepositions of five letters or more, and MLA editorial guidance generally lowercases internal prepositions regardless of length.
APA title case capitalizes the first word, the first word of a subtitle, major words, and words of four letters or more while keeping short minor words lowercase in ordinary mid-title positions.
Chicago 18 uses title case for titles of works and changed a long-standing rule: prepositions of five letters or more are now capitalized. Shorter prepositions generally remain lowercase internally, while first and last words are capitalized and “to” remains lowercase as an infinitive marker in ordinary mid-title use.
MLA 9 describes title style as capitalizing the first word, last word, and all principal words. MLA’s public Style Center also documents the traditional lowercase treatment of internal prepositions, but its detailed preposition article is edition-labeled for MLA 8, so this engine does not yet treat the full MLA 9 converter profile as complete.
APA capitalizes “Among” internally because it has at least four letters. Chicago 18 also capitalizes it because prepositions of five letters or more are capitalized. MLA ordinarily lowercases internal prepositions, while any principal-word use needs grammatical classification before an automated decision.
Usually no in the middle of a title. “at” is a short preposition: APA lowercases short prepositions of three letters or fewer, Chicago 18 lowercases prepositions of four letters or fewer, and MLA title style normally treats internal prepositions as minor words. The answer depends on the style guide and position, so this page separates APA 7, Chicago 18, and MLA guidance instead of applying one generic title-case list.
Usually no in the middle of a title. “by” is a short preposition: APA lowercases short prepositions of three letters or fewer, Chicago 18 lowercases prepositions of four letters or fewer, and MLA title style normally treats internal prepositions as minor words. The answer depends on the style guide and position, so this page separates APA 7, Chicago 18, and MLA guidance instead of applying one generic title-case list.
APA capitalizes “Despite” internally because it has at least four letters. Chicago 18 also capitalizes it because prepositions of five letters or more are capitalized. MLA ordinarily lowercases internal prepositions, while any principal-word use needs grammatical classification before an automated decision.
