List of classical music sub-titles, nicknames and non-numeric titles

This is an alphabetically ordered list of sub-titles, nicknames and non-numeric titles that have been applied to classical music compositions of types that are normally identified only by some combination of number, key and catalogue number. These types of compositions include: symphony, concerto, sonata, and standard chamber music combinations (string strio, quartet, quintet, sextet, etc.; piano trio, quartet, quintet, sextet, etc.), among others.
A sub-title is a subsidiary name given to a work by the composer, and considered part of its formal title, such as:
A nickname is a name that is "not" part of the title given by the composer, but has come to be popularly associated with the work, such as: 
A non-numeric title is a formal title that departs from the usual sequential numbering of works of the same type, such as:
Background.
Many classical compositions belong to a numbered series of works of a similar type by the same composer. For example, Beethoven wrote 9 symphonies, 10 violin sonatas, 32 piano sonatas, 5 piano concertos, 16 string quartets, 7 piano trios and other works, all of which are numbered sequentially within their genres and generally referred to by their sequence numbers, keys and opus numbers. For example, the 6th of his violin sonatas is referred to as: "Violin Sonata No. 6 in A major, Op. 30, No. 1".
However, some of these works were also given descriptive sub-titles by Beethoven himself: for example, he sub-titled the 3rd Symphony "Eroica", and the 6th Symphony "Pastoral".
Others were given nicknames by publishers or others: for example, the Piano Sonata No. 14 is called "Moonlight" and the Piano Trio No. 7 is known as the "Archduke".
In other cases, a composer gives a work a title without any number, even though he may have written other works of that type with numbers. For example, Tchaikovsky wrote 6 numbered symphonies, but he also wrote the unnumbered "Manfred Symphony" between the 4th and 5th symphonies. A listing of all Tchaikovsky's symphonies would be incomplete without mention of the "Manfred Symphony".
Special cases.
Works such as Vaughan Williams's first three symphonies ("A Sea Symphony", "A London Symphony" and "A Pastoral Symphony") fit into more than one camp. These are true titles, as Vaughan Williams commenced the numbering of his symphonies only from his 4th Symphony. The first three symphonies were, however, retrospectively given numbers by cataloguers. Hence, "A Sea Symphony", for example, is often referred to as his "Symphony No. 1", with the original title being relegated to a sub-title, although that was never Vaughan Williams's own intention or practice.
Other named works excluded.
There are vast numbers of other named compositions that do not qualify for this list. Symphonic poems, concert overtures, suites, variations, operas, ballets, most vocal and choral music, and miscellaneous other works are normally given titles that exclude numbers. Examples of such works would include: 