महाभारतः mahābhārataḥ - book-13, chapter-12, verse-4

अग्निष्टुं नाम राजर्षिरिन्द्रद्विष्टं महाबलः ।
प्रायश्चित्तेषु मर्त्यानां पुत्रकामस्य चेष्यते ॥४॥

4. agniṣṭuṁ nāma rājarṣirindradviṣṭaṁ mahābalaḥ ,
prāyaścitteṣu martyānāṁ putrakāmasya ceṣyate.

4. agniṣṭum nāma rājarṣiḥ indradviṣṭam mahābalaḥ
prāyaścitteṣu martyānām putrakāmasya ca iṣyate

4. mahābalaḥ rājarṣiḥ agniṣṭum nāma indradviṣṭam
martyānām prāyaścitteṣu ca putrakāmasya iṣyate

4. The royal sage, who is very powerful, (performs) the Agniṣṭut (Vedic ritual), which is hated by Indra. This ritual (yajña) is prescribed for the expiation of mortals and for those desiring a son.

Words meanings summery:

• अग्निष्टुम् (agniṣṭum) - The name of the Vedic ritual (yajña) performed by Bhaṅgāśvana (Agniṣṭut (name of a specific Soma ritual))

• नाम (nāma) - by name (indicating the name of the ritual) (name, indeed, by name)

• राजर्षिः (rājarṣiḥ) - The king Bhaṅgāśvana (royal sage, king-sage)

• इन्द्रद्विष्टम् (indradviṣṭam) - The Agniṣṭut (yajña) which is hated by Indra (hated by Indra, inimical to Indra)

• महाबलः (mahābalaḥ) - Referring to the royal sage Bhaṅgāśvana (very powerful, possessing great strength)

• प्रायश्चित्तेषु (prāyaścitteṣu) - in expiations, for atonements

• मर्त्यानाम् (martyānām) - of mortals, among mortals

• पुत्रकामस्य (putrakāmasya) - For Bhaṅgāśvana, who desired a son (of one desiring a son)

• च (ca) - and, also

• इष्यते (iṣyate) - is prescribed (for performance) (is desired, is sought, is performed, is prescribed)

Words meanings and morphology

अग्निष्टुम् (agniṣṭum) - The name of the Vedic ritual (yajña) performed by Bhaṅgāśvana (Agniṣṭut (name of a specific Soma ritual))

(noun)

Accusative, masculine, singular of agniṣṭut

agniṣṭut - name of a Soma ritual (yajña); praising Agni

Compound type : tatpurusha (agni+ṣṭut)

• agni – fire god, fire
  noun (masculine)
• ṣṭut – praising
  adjective (masculine)
  agent noun
  from root stu- (to praise)
  Root: stu (class 2)

Note: Taken as an implied object or subject of description

नाम (nāma) - by name (indicating the name of the ritual) (name, indeed, by name)

(indeclinable)

राजर्षिः (rājarṣiḥ) - The king Bhaṅgāśvana (royal sage, king-sage)

(noun)

Nominative, masculine, singular of rājarṣi

rājarṣi - royal sage, king-sage

Compound type : tatpurusha (rājan+ṛṣi)

• rājan – king, ruler
  noun (masculine)
• ṛṣi – sage, seer
  noun (masculine)

Note: Refers to Bhaṅgāśvana

इन्द्रद्विष्टम् (indradviṣṭam) - The Agniṣṭut (yajña) which is hated by Indra (hated by Indra, inimical to Indra)

(adjective)

Nominative, neuter, singular of indradviṣṭa

indradviṣṭa - hated by Indra, inimical to Indra

past passive participle

Compound: Indra (genitive) + dviṣṭa (P.P.P. of dviṣ)

Compound type : tatpurusha (indra+dviṣṭa)

• indra – Indra (name of a deity), ruler
  proper noun (masculine)
• dviṣṭa – hated, inimical
  adjective (masculine)
  Past Passive Participle
  from root dviṣ (to hate)
  Root: dviṣ (class 2)

Note: Used here as a neuter nominative singular, describing the 'ritual' (yajña)

महाबलः (mahābalaḥ) - Referring to the royal sage Bhaṅgāśvana (very powerful, possessing great strength)

(adjective)

Nominative, masculine, singular of mahābala

mahābala - very powerful, great strength

Compound type : bahuvrihi (mahā+bala)

• mahā – great, large
  adjective
• bala – strength, power
  noun (neuter)

Note: Agrees with `rājarṣiḥ`

प्रायश्चित्तेषु (prāyaścitteṣu) - in expiations, for atonements

(noun)

Locative, neuter, plural of prāyaścitta

prāyaścitta - expiation, atonement, penance

मर्त्यानाम् (martyānām) - of mortals, among mortals

(noun)

Genitive, masculine, plural of martya

martya - mortal, human being

पुत्रकामस्य (putrakāmasya) - For Bhaṅgāśvana, who desired a son (of one desiring a son)

(adjective)

Genitive, masculine, singular of putrakāma

putrakāma - desiring a son

Compound: putra (son) + kāma (desire)

Compound type : tatpurusha (putra+kāma)

• putra – son
  noun (masculine)
• kāma – desire, wish
  noun (masculine)

Note: Can also be used as a noun 'one desiring a son'

च (ca) - and, also

(indeclinable)

इष्यते (iṣyate) - is prescribed (for performance) (is desired, is sought, is performed, is prescribed)

(verb)

3rd person , singular, passive, present (lat) of iṣ

Root: iṣ (class 4)

Note: Passive form of the root iṣ, meaning 'is desired/prescribed/performed'.