Syncopation

n. act of emphasizing the beats or accents that are usually not accented (Music); omission of a letter or sound from the middle of a word (Grammar); change of meter (Poetry)

In music, syncopation is a stress on a normally unstressed beat, or a missing beat where a stressed one would normally be expected. Syncopation is used in many musical styles, including classical music, but it is fundamental in such styles as reggae, ragtime, rap, jump blues,  jazz and often in dubstep. In the form of a back beat, syncopation is used in virtually all contemporary popular music.
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Noun
1. (phonology) the loss of sounds in the interior of a word (as in `fo'c'sle' for `forecastle')
(synonym) syncope
(hypernym) articulation
(derivation) syncopate
(classification) phonology, phonemics
2. a musical rhythm accenting a normally weak beat
(hypernym) rhythm, beat, musical rhythm
(derivation) syncopate
3. music (especially dance music) that has a syncopated rhythm
(hypernym) music
(derivation) syncopate
(classification) music

(n.)
The act of syncopating; the contraction of a word by taking one or more letters or syllables from the middle; syncope.
  

(n.)
The act of syncopating; a peculiar figure of rhythm, or rhythmical alteration, which consists in welding into one tone the second half of one beat with the first half of the beat which follows.
  

Synonyms and related words:
acid rock, andante tempo, avant-garde jazz, ballroom music, beat, bebop, boogie-woogie, bop, compound time, country rock, dance music, dances, duple time, folk rock, hard rock, hot jazz, jazz, jive, largo, mainstream jazz, march tempo, mixed times, musical suite, presto, rag, ragtime, rhythm-and-blues, rock, rock-and-roll, rubato, sextuple time, simple time, suite, suite of dances, swing, syncopated music, syncope, tempo, tempo rubato, the new music, three-quarter time, time, time pattern, timing, triple time, triplet, two-four time, waltz time|