augmented sixth
C2 (Proficient)Exclusively technical/musical. Highly formal and domain-specific.
Definition
Meaning
A specific chord in music theory, built on the flattened sixth scale degree, containing an augmented sixth interval that resolves outwards to an octave on the dominant.
In broader, non-musical contexts, it can describe any sixth that has been increased by a semitone, but this usage is rare. The term is overwhelmingly technical.
Linguistics
Semantic Notes
Not a general adjective + noun phrase (e.g., 'an augmented sixth sense'). It is a fixed, compound musical term referring to both an interval and a family of chords (Italian, French, German augmented sixth chords).
Dialectal Variation
British vs American Usage
Differences
No lexical or conceptual differences. Spelling of related terms may differ (e.g., 'flattened' vs. 'flatted sixth'), but 'augmented sixth' is invariant.
Connotations
Identical technical connotations in both varieties.
Frequency
Frequency is identical—zero in general language, high within music theory discourse.
Vocabulary
Collocations
Grammar
Valency Patterns
The [composer] used an augmented sixth to modulate to the [key].An augmented sixth [resolves/leads] to the dominant.The [Italian/German/French] augmented sixth is spelled with [notes].Vocabulary
Synonyms
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Not used.
Academic
Exclusively used in musicology, harmonic analysis, and composition textbooks.
Everyday
Virtually never used.
Technical
Core term in music theory for describing a specific harmonic function and voice-leading pattern, especially in common-practice period tonality.
Examples
By Part of Speech
adjective
British English
- The augmented-sixth sonority is unmistakable.
- That's a classic augmented-sixth function.
American English
- The augmented-sixth sound is very dramatic.
- It's an augmented-sixth kind of tension.
Examples
By CEFR Level
- The composer used an augmented sixth chord to create tension before the final chorus.
- Can you hear how this chord, an augmented sixth, wants to resolve outwards?
- The German augmented sixth, with its additional perfect fifth, has a richer texture than its Italian counterpart.
- Analysing the recitative, we find an enharmonically respelled augmented sixth facilitating a remote modulation.
Learning
Memory Aids
Mnemonic
Think of it as the 'expanding sixth': the two notes of the interval (like A♭ and F♯) are forced to move outward (augment) to reach an octave on the dominant note (G).
Conceptual Metaphor
HARMONY AS JOURNEY / TENSION AND RELEASE: The chord is a point of intense 'chromatic tension' that must 'resolve' outwards, like a spring being released.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not translate word-for-word as 'увеличенная шестая'. Use the established calque 'увеличенный секстаккорд' or specific terms: 'итальянский секстаккорд', 'французский секстаккорд', 'немецкий секстаккорд'.
- The interval is 'увеличенная секста', but the chord is the common referent.
Common Mistakes
- Using it as a general adjective ('an augmented sixth attempt').
- Confusing it with a dominant seventh chord due to enharmonic spelling.
- Misidentifying the scale degree—it is built on the *flattened* submediant (♭VI), not the natural sixth.
Practice
Quiz
On which scale degree is the root of a typical augmented sixth chord built?
FAQ
Frequently Asked Questions
It has a dominant *function* (it strongly resolves to the dominant chord, V), but it is not built on the dominant scale degree. It is a pre-dominant chromatic chord.
They are three types of augmented sixth chords, differing in their third and fifth components. The Italian has a third; the French adds an augmented fourth; the German adds a perfect fifth (which can sound like a dominant seventh if spelled enharmonically).
Yes, as a melodic or harmonic interval in very chromatic or atonal music, but in common-practice tonality, it is almost exclusively heard within the context of the augmented sixth chord progressing to the dominant.
The name comes from the interval between the two essential, character-defining notes: the flattened sixth scale degree (e.g., A♭) and the raised fourth (e.g., F♯). This interval is an augmented sixth (A♭ to F♯), which distinguishes it from a minor seventh (A♭ to G♭).