List of Latin phrases (Q)

Characteristic features

Latin phrases often appear as short formulas, abbreviations, or proverbs. They may be cited with capitals or periods (for example Q.E.D. for quod erat demonstrandum). In modern usage the original grammar is usually preserved, but meanings can shift; for instance quid pro quo in English commonly implies an illicit or transactional exchange beyond its literal "something for something" translation.

Notable Q phrases and translations

• Quod erat demonstrandum (Q.E.D.) — "which was to be demonstrated." Traditionally used at the conclusion of a proof in mathematics and logic.
• Quod erat faciendum (Q.E.F.) — "which was to be done." A variant used to close constructions or geometric problems where an action was required.
• Quid pro quo — "something for something" or "this for that." A phrase for reciprocal exchange, used in law, diplomacy and everyday speech.
• Quod vide (q.v.) — "which see." A cross-reference marker in scholarly texts directing the reader to another entry.
• Quis custodiet ipsos custodes? — "Who will guard the guards themselves?" A famous rhetorical question about accountability, attributed to the Roman poet Juvenal.
• Quod scripsi, scripsi — "What I have written, I have written." A traditional formula attributed in Christian tradition to Pontius Pilate; used to signal finality.
• Quod licet Iovi non licet bovi — "What is permitted to Jupiter is not permitted to a bull." A proverb warning that powerful persons enjoy privileges denied to others.
• Quodlibet — "whatever you please." Historically applied to a disputation or a musical medley; still used to indicate miscellaneous choice.
• Quasi — "as if" or "seemingly." A versatile particle used in philosophical and everyday Latin-derived English.

History and evolution

Many Q-phrases are survivals from classical Roman literature, medieval scholasticism and ecclesiastical Latin. The transmission of Greek rhetorical and scientific terminology into Latin influenced form and usage, and medieval universities helped fix some set phrases (for example the scholastic quodlibet). Abbreviations such as Q.E.D. became conventional in printed scholarly works from the Renaissance onward.

Uses and notable distinctions

In modern English some phrases remain technical (mathematical proofs use Q.E.D.), while others have broadened into idioms (quid pro quo). Reference abbreviations like q.v. are common in bibliographies. Pronunciation, punctuation and emphasis vary by tradition—classical, medieval or ecclesiastical—and editors sometimes supply macrons or italics to indicate Latin forms.

Further reading and links

For translations and parallel lists consult reference pages for Latin phrases and translation tools: translations, Latin phrase guides, and scholarly lexica at language resources. For rhetorical background see classical rhetoric pages at rhetoric resources and overviews of Roman literature at Roman literature. For the comprehensive alphabetical index see the main compilation: List of Latin phrases.