ربع

رُبْعٌ ذ (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 pl. of رُبْعٌ and ↓ رُبُعٌ is أَرْبَاعٌ [a pl. of pauc.] (Msb, TA) and رُبُوعٌ [a pl. of mult]: (TA:) and that of ↓ رَبِيعٌ is رُبُعٌ (K.) ― -b2- 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.] ― -b3- أَرْبَاعُ الرَّأْسِ The [ four ] regions of the head. (TA.)