Terms for melody, harmony, rhythm, texture, tonality, voicing, color, dynamics, and form:

Melody

augmentation
write/play in longer (slower) note values
articulation
staccato, legato, tenuto, etc.
breathing
silences between sounds
cycles/rotations
cycling through figures; e.g., Alberti bass
diminution
write/play in faster note values
directed motion
motion towards a goal
elision
subtract note/s
fragmentation
a segment of a theme
hard/soft edge
harder or softer definition
interpolation
interject new (aDTed) tones
interruption
tones that substitute for expected goal tones; e.g., climax of Wagner's Tristan & Isolde, act 2
interval contraction
smaller intervals, same contour; e.g., Liszt's Les Preludes
interval expansion
larger intervals, same contour; e.g., Liszt's Les Preludes
inversion
mirrored contour; e.g., subject and inversion in Bartok's Music for Strings, Percussion and Celeste, first movement
isomelos
same notes, different rhythm; used constantly in dodecaphony
microtones
intervals smaller than a semitone
non-tonal scales
scale structures that are symmetric in content; e.g., whole-tone scale, which has no differences to imply a tonic
octave displacement
melody with tones played in differing octave registers; occurs frequently ion Webern's music
ornamentation
embellishment of a given figure or framework, such as a trill
permutation
change the order of pitches
prolongation
goal tones used as skeleton for long lines
retrograde inversion
a backwards inversion (much used in dodecaphony)
retrograde
a theme backwards
serial technique
a constant ordering of pitch-classes, rhythms, etc.
shaping
a dynamic/time contour
subcomplex
extracted non-consecutive tones as a nucleus
subtraction /elision
a theme/motive with subtracted tones
translation
figures that are repeated in time or pitch
transposition
a figure higher or lower in pitch

Harmony

accompaniment/framework
skeletal backdrop for other instruments
clusters/sound mass
large secundal chords
harmonic rhythm
rate of harmonic change
minimal process
repetitive process on small number of elements; e.g., Terry Riley's In C; Phillip Glass's Koyanisqatsi
non-tertian chords
chord structures not based on thirds; e.g., quartal chords
nucleus
a special set used as a primary focus; e.g., A, C, C# in Scriabin's Op. 74/4
ostinati
obstinate, unchanging figures or aspects, usually in the bass
stasis
a static figure, commonly background; e.g., repeating chord figure
substitution
a chord, line, etc. that substitutes for others; e.g., ii for IV
translation
figures that are repeated in time or pitch; e.g., sequence
unravelling
an arpeggiation or spinning out of structures; e.g., chord arpeggiation

Rhythm

ametric
without any feeling of meter; e.g., chant
augmentation
motive at a slower tempo; longer notes; e.g., Bach's fugues
automoton
like a machine; mechanically
diminution
a motive at a faster tempo; e.g., Rachmaninov's Isle of the Dead (uses Dies Irae)
hemiola
change of meter within another; e.g., duple within triple (Brahms); similar to multimeter, but without a change of meter signature; also, used for unwritten polymeters (Schubert)
homorhythm
simultaneous ensemble attacks
isorhythm
changing pitches, same rhythm; e.g., isorhythmic motets
isomelos
changing rhythm, same pitches
metric modulation
changing the length of the pulse group
multi-meter
changing meters; 4/4 to 5/8 to 6/8, etc.; e.g., Stravinsky's La Sacre du Printemps (Rite of Spring)
physical action
reflexive, muscular movements
polymeters
different meters simultaneously; e.g., 2/4 + 3/4; e.g., Ives's Scherzo, Over the Pavements
polyrhythm
distinctly divergent simultaneous rhythmic patterns; e.g., Ives's Scherzo, Over the Pavements
suspended time
very long static events, with nothing much else happening
syncopation
unexpected rhythms; e.g., Ives's Scherzo, Over the Pavements
tempo
faster, aggitated, or slower, calmer
tempo modulation
periodically accel. or decel.

Texture

imitation
statements of the same idea by successive voices, normally in counterpoint; Renaissance motets
isotrophy
harmonic planes or blocks of sound moving in opposite directions
layering/stratification
repetitions in each part layered with other parts; e.g., Berlioz's Requiem, the Offertory
planing
moving chords in parallel motion; e.g., in Debussy's Preludes
polarization
one of two opposites; e.g., antiphony; e.g., Bartok's Music for Strings, Percussion and Celeste
texture change
dropping in or out; e.g., aDTing/subtracting voices/instruments; e.g., Ravel's Bolero
texture modulation
gradually thinning or thickening; e.g., Ravel's Bolero
density
increasing or decreasing the number of notes per unit time or space; e.g., Bartok's Music for Strings, Percussion and Celeste

Tonality

atonality
(see pantonality)
modality
use of modes other than major/minor; e.g., Hungarian folksongs
modulation
a changing tonal focus; a change of key
pandiatonic
all tones of a diatonic scale treated with equal importance
pantonality
all (12) tones with equal importance
polymodality
more than one mode at a time; e.g., Dorian and Major simultaneously
polytonality
more than one tonic at the same time; e.g., Stravinsky's La Sacre du Printemps
tonal axis
tonic/dominant syntax/substitution

Voicing

crossing voices
crossing over or under a given voice
doublings
dup.pc , parallel motion
voicing
open/close, smooth/disjunct
underlap
crossing under a given line

Color

electronic alteration
filtration or other electronic changes
extended techniques
unusual playing methods on conventional instruments; e.g., Berio's Sequenza's and Visage; Cowell's Banshee, Cage's Sonatas and Interludes for prepared piano
klangfarbenmelodie
alternating melodic tones with other instrument/s; e.g., Webern's orchestration of Bach's Ricecar from The Musical Offering, and Symphony
metamorphosis
changing one idea gradually into another; e.g., Liszt's Les Preludes, Bartok's String Quartet No. 2
multiphonics
chords or harmonic intervals produced from harmonics
pointillism
short single bursts of instrumental color interjected among others; e.g., Webern's Concerto, op. 24
sprechstimme
nearly spoken song; e.g., Schoenberg's Pierrot Lunaire
timbre modulation
changing the dynamic balance; e.g., Carter's Etude #7 from Eight Etudes and a Fantasy

Dynamics

balance
louder or softer compared with other parts
dynamic modulation
solo cresc./decresc. differing with other parts
terraced dynamics
a suDTen change in loudness level

Form

indeterminacy
sounds not under control of a composer and performer; e.g., Cage's 4'33"
moment form
constant figures used to unify short sections; e.g., Stockhausen Momente
overlap
dovetailing old and new ideas in transition
parody
quotations of sections of pre-existing music; e.g., Schubert's March Militaire in Stravinsky's Circus Polka
stochastic (Xenakis)
a controlled chance structure using probability theory
surprise
a suDTen contrast; e.g., Haydn's Surprise Symphony
transition
a bridge from from one idea to another; e.g., Beethoven's Symphony No 5, 3rd to 4th movements
union
a joining together of non-consecutive structures

Miscellaneous

antiphony
spatial responses
beating
tone slightly out of unison with other parts
debate
argumentatively
spatial modulation
motion during performance
synaesthesia
a mixing of sensory stimuli (smell, sight, touch, etc.)