महाभारतः mahābhārataḥ - book-15, chapter-22, verse-12

आयसं हृदयं नूनं मन्दाया मम पुत्रक ।
यत्सूर्यजमपश्यन्त्याः शतधा न विदीर्यते ॥१२॥

12. āyasaṁ hṛdayaṁ nūnaṁ mandāyā mama putraka ,
yatsūryajamapaśyantyāḥ śatadhā na vidīryate.

12. āyasam hṛdayam nūnam mandāyāḥ mama putraka
yat sūryajam apaśyantyāḥ śatadhā na vidīryate

12. putraka mama mandāyāḥ hṛdayam nūnam āyasam
yat sūryajam apaśyantyāḥ śatadhā na vidīryate

12. O my son, my foolish heart is certainly made of iron, because even though I failed to acknowledge the son of the sun (Karṇa), it does not burst into a hundred pieces.

Words meanings summery:

• आयसम् (āyasam) - made of iron (iron, made of iron)

• हृदयम् (hṛdayam) - heart (heart, mind)

• नूनम् (nūnam) - certainly (surely, certainly, indeed)

• मन्दायाः (mandāyāḥ) - of me, the foolish one (of the foolish one, by the foolish one)

• मम (mama) - my (Kuntī's) (my, of me)

• पुत्रक (putraka) - O son (referring to Yudhiṣṭhira) (O son, little son)

• यत् (yat) - because (because, that (which))

• सूर्यजम् (sūryajam) - Karṇa, the son of the Sun god (son of Sūrya (the Sun god))

• अपश्यन्त्याः (apaśyantyāḥ) - of me, who failed to acknowledge (of the one not seeing/acknowledging)

• शतधा (śatadhā) - into a hundred pieces (in a hundred ways, into a hundred pieces)

• न (na) - not (not, no)

• विदीर्यते (vidīryate) - does not burst (bursts, breaks apart)

Words meanings and morphology

आयसम् (āyasam) - made of iron (iron, made of iron)

(adjective)

neuter, singular of āyasa

āyasa - made of iron, iron-like, hard

Derived from ayas (iron) + aṇ suffix.

Note: Agrees with hṛdayam.

हृदयम् (hṛdayam) - heart (heart, mind)

(noun)

neuter, singular of hṛdaya

hṛdaya - heart, mind, soul, core

Root: hṛ (class 1)

Note: Subject of the sentence.

नूनम् (nūnam) - certainly (surely, certainly, indeed)

(indeclinable)

मन्दायाः (mandāyāḥ) - of me, the foolish one (of the foolish one, by the foolish one)

(adjective)

Genitive, feminine, singular of mandā

manda - slow, dull, foolish, weak

Root: mand (class 1)

Note: Agrees with mama.

मम (mama) - my (Kuntī's) (my, of me)

(pronoun)

Genitive, singular of aham

aham - I, myself

Note: Possessive.

पुत्रक (putraka) - O son (referring to Yudhiṣṭhira) (O son, little son)

(noun)

Vocative, masculine, singular of putraka

putraka - son (diminutive/endearing), little son

Derived from putra (son) + ka (diminutive suffix).

यत् (yat) - because (because, that (which))

(indeclinable)

Relates to tad (that).

सूर्यजम् (sūryajam) - Karṇa, the son of the Sun god (son of Sūrya (the Sun god))

(noun)

Accusative, masculine, singular of sūryaja

sūryaja - born of the sun, son of Sūrya

From sūrya (sun) + ja (born from).

Compound type : tatpuruṣa (sūrya+ja)

• sūrya – sun, Sun god
  noun (masculine)
• ja – born, produced from
  adjective
  Derived from root jan (to be born)
  Root: jan (class 4)

Note: Object of apaśyantyāḥ.

अपश्यन्त्याः (apaśyantyāḥ) - of me, who failed to acknowledge (of the one not seeing/acknowledging)

(adjective)

Genitive, feminine, singular of apaśyantī

apaśyantī - not seeing, not perceiving, unobservant, neglecting, failing to acknowledge

Present Active Participle

Feminine form of apaśyat, from a (not) + paśyat (seeing). paśyat is from root dṛś (to see) in present stem.

Compound type : nañ-tatpuruṣa (a+paśyantī)

• a – not, un-
  indeclinable
• paśyantī – seeing, perceiving
  adjective (participle) (feminine)
  Present Active Participle
  Feminine of paśyat, present participle of dṛś (to see).
  Root: dṛś (class 1)

Note: Grammatically agrees with mandāyāḥ mama.

शतधा (śatadhā) - into a hundred pieces (in a hundred ways, into a hundred pieces)

(indeclinable)

Derived from śata (hundred) + dhā suffix.

न (na) - not (not, no)

(indeclinable)

विदीर्यते (vidīryate) - does not burst (bursts, breaks apart)

(verb)

3rd person , singular, passive, present (laṭ) of dṝ

Derived from vi + dṝ (to tear, burst) in passive voice. Root dṝ is 9th class in active, but here it's ātmanepada. vidīryate is present passive 3rd singular.

Prefix: vi

Root: dṝ (class 9)

Note: Subject is hṛdayam.