An iamb (ˈaɪæm ) or iambus is a metrical foot used in various types of poetry. Originally the term referred to one of the feet of the quantitative meter of classical Greek prosody: a short syllable followed by a long syllable (as in καλή () "beautiful (f.)"). This terminology was adopted in the description of accentual-syllabic verse in English, where it refers to a foot comprising an unstressed syllable followed by a stressed syllable (as in abóve). Thus a Latin word like íbī, because of its short-long rhythm, is considered by Latin scholars to be an iamb, but because it has a stress on the first syllable, in modern linguistics it is considered to be a trochee.
Iambus (genre)
R. S. P. Beekes has suggested that the ἴαμβος iambos has a Pre-Greek origin. An old hypothesis is that the word is borrowed from Phrygian or Pelasgian, and literally means "Einschritt", i. e., "one-step", compare dithyramb and thriambus, but H. S. Versnel rejects this etymology and suggests instead a derivation from a cultic exclamation. The word may be related to Iambe, a Greek minor goddess of verse, especially scurrilous, ribald humour. In ancient Greece iambus was mainly satirical poetry, lampoons, which did not automatically imply a particular metrical type. Iambic metre took its name from being characteristic of iambi, not vice versa.
In accentual-syllabic verse and in modern linguistics an iamb is a foot that has the rhythmic pattern:
Using the 'ictus and x' notation (see systems of scansion for a full discussion of various notations) we can write this as:
The word 'attempt' is a natural iamb:
In phonology, an iambic foot is notated in a flat representation as (σ'σ) or as foot tree with two branches W and S where W = weak and S = strong.
Iambic pentameter is one of the most commonly used measures in English and German poetry, for instance it can be found Shakespeare's Sonnets. A line of iambic pentameter comprises five consecutive iambs.
Iambic trimeter is the metre of the spoken verses in Greek tragedy and comedy, comprising six iambs—as one iambic metrum consisted of two iambs.