रुद्र

Possibly from the root रुद् (rud, “to roar”) +‎ -र (-ra), but this could be a later folk etymology of the name of the god. Mayrhofer suggest a connection with रोदसी (ródasī, dual), of unclear meaning.

• (Vedic) IPA^(key): /ɾud.ɾɐ́/, /ɾu.dɐ.ɾɐ́/
• (Classical Sanskrit) IPA^(key): /ˈɾud̪.ɾɐ/

रु॒द्र • (rudrá) stem (root रुद्)

1. roaring, howling

रु॒द्र • (rudrá) stem, m (root रुद्) (metrical Vedic sometimes rudará)

1. (Vedic religion) Rudra, father of the Maruts, deity of the winds and storms.
   • c. 1700 BCE – 1200 BCE, Ṛgveda 1.114.3:

     अ॒श्याम॑ ते सुम॒तिं दे॑वय॒ज्यया॑ क्ष॒यद्वी॑रस्य॒ तव॑ रुद्र मीढ्वः।
     सु॒म्ना॒यन्निद्विशो॑ अ॒स्माक॒मा च॒रारि॑ष्टवीरा जुहवाम ते ह॒विः॥

     aśyā́ma te sumatíṃ devayajyáyā kṣayádvīrasya táva rudra mīḍhvaḥ.
     sumnāyánnídvíśo asmā́kamā́ carā́riṣṭavīrā juhavāma te havíḥ.

     Rudra, showerer of benefits, may we obtain, through our worship of the gods, the favour of you, who are the destroyer of heroes;come to our posterity, purposing to promote their happiness, while we, having our sons in safety, offer you oblations.

2. roarer or howler.
3. The number ‘eleven’ (from the 11 rudras).
4. The eleventh.
5. (music) a kind of stringed instrument (cf. रुद्री and रुद्रवीणा)

• Monier Williams (1899) “रुद्र”, in A Sanskrit–English Dictionary, , new edition, Oxford: At the Clarendon Press, →OCLC, page 883, columns 1-2.
• Mayrhofer, Manfred (1996) “rudrá-”, in Etymologisches Wörterbuch des Altindoarischen [Etymological Dictionary of Old Indo-Aryan]‎ (in German), volume 2, Heidelberg: Carl Winter Universitätsverlag, pages 452-3