رُبْعٌ
1.
(S, Mgh, Msb, K) and
رُبُعٌ, (S, Msb, K,) the former a contraction of the latter, (Msb,) [which is the more chaste, but the former is the more common,] A fourth part; (S, Msb, K;) one of four parts; (Mgh;;) as also
رَبِيعٌ, (Msb, K,) like عَشِيرٌ; (TA;) and
مِرْبَاعٌ, like مِعْشَارٌ: (Ktr, and S:) or the last signifies, (Msb, K,) or signifies also, (S,) the fourth part of the spoil, which the chief used to take (S, Msb, K) in the Time of Ignorance: (K:) the plural of رُبْعٌ and
رُبُعٌ is أَرْبَاعٌ [a plural of pauc.] (Msb, TA) and رُبُوعٌ [a plural of mult]: (TA:) and that of
رَبِيعٌ is رُبُعٌ (K.)
2.
الرُّبْعُ الهَاشِمِىُّ
The same as the
صَاع; because the قَفِيز is twelve times what is termed مَنّ: but الرُّبْعُ الحَجَّاجِىُّ is the same as the
مُدّ, which is a quarter of what is termed
الصَّاعُ
الحَجَّاجِىُّ. (Mgh.) [In Egypt, the رُبْع is the fourth part of a
وُيْبَة, q. v.]
3.
أَرْبَاعُ الرَّأْسِ
The [four] regions of the head. (TA.)