शिरस्

Sanskrit

From Proto-Indo-Iranian *ćŕ̥Has, from Proto-Indo-European *ḱŕ̥h₂-os, from *ḱerh₂- (“head”); see there for more. Cognate with Avestan 𐬯𐬁𐬭𐬀 (sāra), Latin cerebrum.

शिरस् • (śíras) stem, n

(anatomy) head, skull
- c. 1700 BCE – 1200 BCE, Ṛgveda 3.51:
  इ॒दं ह्यन्वोज॑सा सु॒तं रा॑धानां पते । पिबा॒ त्व१॒॑स्य गि॑र्वणः ॥ यस्ते॒ अनु॑ स्व॒धामस॑त्सु॒ते नि य॑च्छ त॒न्वं॑ । स त्वा॑ ममत्तु सो॒म्यं ॥ प्र ते॑ अश्नोतु कु॒क्ष्योः प्रेन्द्र॒ ब्रह्म॑णा॒ शिरः॑ । प्र बा॒हू शू॑र॒ राध॑से ॥
  idáṃ hyánvójasā sutáṃ rādhānāṃ pate. píbā tvàsyá girvaṇaḥ. yáste ánu svadhā́másatsuté ní yaccha tanvàṃ. sá tvā mamattu somyáṃ. prá te aśnotu kukṣyóḥ préndra bráhmaṇā śíraḥ. prá bāhū́ śūra rā́dhase.
  So, Lord of affluent gifts, this juice hath been pressed for thee with strength. Drink of it, thou who lovest song. Incline thy body to this juice which suits thy Godlike nature well. May it cheer thee who lovest it. Brave Indra, let it work through both thy flanks, and through thy head by prayer, and through thine arms, to prosper us.
the upper end or highest part of anything, top, peak, summit, pinnacle, acme
the forepart or van (of an army)
the beginning (of a verse)
the head, leader, chief, foremost, first (of a class)

Neuter as-stem declension of शिरस् (śíras)
	Singular	Dual	Plural
Nominative	शिरः śíraḥ	शिरसी śírasī	शिरांसि śírāṃsi
Vocative	श��रः śíraḥ	शिरसी śírasī	शिरांसि śírāṃsi
Accusative	शिरः śíraḥ	शिरसी śírasī	शिरांसि śírāṃsi
Instrumental	शिरसा śírasā	शिरोभ्याम् śírobhyām	शिरोभिः śírobhiḥ
Dative	शिरसे śírase	शिरोभ्याम् śírobhyām	शिरोभ्यः śírobhyaḥ
Ablative	शिरसः śírasaḥ	शिरोभ्याम् śírobhyām	शिरोभ्यः śírobhyaḥ
Genitive	शिरसः śírasaḥ	शिरसोः śírasoḥ	शिरसाम् śírasām
Locative	शिरसि śírasi	शिरसोः śírasoḥ	शिरःसु śíraḥsu

Ardhamagadhi Prakrit: 𑀲𑀺𑀭 (sira)
- Awadhi: सिर (sir)
Dardic:
- Kashmiri: [script needed] (hīrü)
- Northwest Pashayi: [script needed] (šīr)
Helu Prakrit:
- Sinhalese: සිර (sira)
Magadhi Prakrit: 𑀲𑀺𑀭 (sira)
- Assamese: সিৰ (xir)
- Bengali: শির (śir)
- Maithili: सिर (sir)
- Odia: ସିର (sira)
Pali: siras
Sauraseni Prakrit: 𑀲𑀺𑀭 (sira)
- Garhwali: सिर (sir)
- Gujarati: સિર (sir)
- Hindustani:
  Hindi: सिर (sir)
  
  Urdu: سر (sir)
- Kumaoni: सिर (sir)
- Nepali: सिर (sira)
- Punjabi: ਸਿਰ (sir)
- Romani: śero, shero (Anglicized), šero (Pan-Vlax)
  - → Hungarian: séró

Monier Williams (1899) “शिरस्”, in A Sanskrit–English Dictionary, […], new edition, Oxford: At the Clarendon Press, →OCLC, page 1072/2.
Turner, Ralph Lilley (1969–1985) “śíras”, in A Comparative Dictionary of the Indo-Aryan Languages, London: Oxford University Press
Mayrhofer, Manfred (1996) Etymologisches Wörterbuch des Altindoarischen [Etymological Dictionary of Old Indo-Aryan]‎^[1] (in German), volume 2, Heidelberg: Carl Winter Universitätsverlag, pages 638-639