1. rtü-
rtü- m. richtige Zeit, bestimmte Zeit, Regel, Menstruationsregel (RV +), rtuthä Adv. regelrecht, gehörig, zur rechten Zeit (RV +), rtviya- Adj. rechtzeitig, regelrecht, rrv(i)ya- menstruierend (RV +, s. AiGr II 2,360,717,816); artavd- m. Jahresabschnitt, Zusammenfassung von Zeitabschnitten (AV +); zu rtvij- s. besonders. - Ni., vgl. die Verweise bei Tu S. 117b. - lir., vgl. jav. raru- m. Zeitabschnitt, Zeitraum, … — [Mayrhofer, s.v. rtü-, p. 312]
2. ṛtu
ṛtu (us), m. ( Uṇ. i, 72 ) any settled point of time, fixed time, time appointed for any action ( esp. for sacrifices and other regular worship), right or fit time, RV. ; AV. ; VS.
3. ṛtu
an epoch, period ( esp. a division or part of the year), season (the number of the divisions of the year is in ancient times, three, five, six, seven, twelve, thirteen, and twenty-four; in later time six seasons are enumerated, viz. Vasanta , ‘spring’; Grīṣma , ‘the hot season’; Varṣā s ( f. pl. nom. ), ‘the rainy season’ Śarad , ‘autumn’; Hemanta , ‘winter’; and Śiśira , ‘the cool season’; the seasons are not unfrequently personified, addressed in Mantra s, and worshipped by libations), RV. ; AV. ; VS. &c., MBh. ; Mn. &c.
4. ṛtu
the menstrual discharge (in women), the time after the courses (favourable for procreation; according to Bhpr. sixteen days after their appearance), Suśr. ; MBh. ; Mn. &c.