Ruba'ee

Rubāʿī (from Arabic: رباعی‎‎ rubāʿiyy, plural رباعيات rubāʿiyāt) is the term for a quatrain, a poem or a verse of a poem consisting of four lines. It refers specifically to a form of Persian poetry, or its derivative form in English and other languages

In classical Persian poetry, the ruba'i is written as a four-line (or two-couplet) poem, with a rhyme-scheme AABA or AAAA.

This is an example of a ruba'i from Rūmī's Dīwān-i Shams:

Anwār-i Ṣalāḥ-i Dīn bar angēkhta bād
Dar dīda u jān-i ʿāshiqān rēkhta bād
Har jān ki laṭīf gasht u az luṭf guzasht
Bā khāk-i Ṣalāḥ-i Dīn dar āmēkhta bād

May the splendors of Salahuddin be roused,
And poured into the eyes and souls of the lovers.
May every soul that has become refined and has surpassed refinement
Be mingled with the dust of Salahuddin!

The usual metre of a Persian ruba'i, which is used for all four lines of the above quatrain by Rumi, is as follows:

In the above scheme, "–" represents a long syllable, and "u" a short one. As variations of this scheme, any sequence of – u can be replaced by a single "overlong" syllable, such as gēkh, tīf, luṭf in the poem above, containing either a long vowel followed by a consonant other than "n", or a short vowel followed by two consonants. An overlong syllable can also freely be substituted for the final syllable of the line, as with bād above.

Another variation is that occasionally a sequence of two short syllables (u u) can be replaced by a single long one (–).

A third variation is to use the same metre as above, but with the eighth and ninth syllables reversed:

The verse form AABA as used in English verse is known as the Rubaiyat Quatrain due to its use by Edward FitzGerald in his famous 1859 translation, Rubaiyat of Omar Khayyam. Algernon Charles Swinburne, one of the first admirers of FitzGerald's translation of Khayyam's medieval Persian verses, was the first to imitate the stanza form, which subsequently became popular and was used widely, as in the case of Robert Frost's 1922 poem "Stopping by Woods on a Snowy Evening".

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