Tawil
Ṭawīl (, literally 'long'), or al-Ṭawīl (), is a meter used in classical Arabic poetry. It comprises distichs ("bayt") of two 'lines'—in Arabic usually written side by side, with a space dividing them, the first being called the "sadr" (صدر, literally "chest") and the other the "ʿajuz" (عجز, literally "belly"). Its basic form is as follows (the symbol "–" representing a long syllable, "⏑" representing a short syllable, and "x" representing a syllable that can be short or long): This form can be exemplified through the traditional mnemonic "" (). The final syllable of every distich rhymes throughout the whole poem; a long  poem might comprise a hundred distichs. In Classical verse, each distich is a complete syntactic unit. Variations. The "Encyclopaedia of Islam" records three sub-types of "ṭawīl" hemistich, of which the second is the most common: In the rare cases where a poem requires rhyme at the end of each hemistich, the last foot of the first hemistich has the same pattern as the last foot of the second, to enable the rhyme. In ancient poetry, the first unstressed syllable of the line is sometimes omitted, and the second foot of each hemistich can be | ⏑ – ⏑ – | instead  of | ⏑ – – – |. Occurrence. "Ṭawīl" was one of the most popular metres in early classical Arabic poetry, comprising over half the surviving corpus of pre-Islamic poetry. One early exponent was Imru' al-Qais, whose "Mu‘allaqa" is in the metre. Its famous opening distich runs: Stay—Let us weep at the remembrance of our beloved, at the sight of the station where her tent was raised, by the edge of yon bending sands between Dahul and Haumel. "Ṭawīl" is seldom used in modern Arabic poetry, but a similar pattern is found in Nabaṭī poetry, and this is sometimes thought  of as an acephalous, catalectic "ṭawīl": | – – ⏑ – – – ⏑ – – ⏑ – – |.