महाभारतः mahābhārataḥ - book-14, chapter-95, verse-17

यदि द्वादशवर्षाणि न वर्षिष्यति वासवः ।
चिन्तायज्ञं करिष्यामि विधिरेष सनातनः ॥१७॥

17. yadi dvādaśavarṣāṇi na varṣiṣyati vāsavaḥ ,
cintāyajñaṁ kariṣyāmi vidhireṣa sanātanaḥ.

17. yadi dvādaśavarṣāṇi na varṣiṣyati vāsavaḥ
cintāyajñaṃ kariṣyāmi vidhiḥ eṣaḥ sanātanaḥ

17. yadi vāsavaḥ dvādaśavarṣāṇi na varṣiṣyati
cintāyajñaṃ kariṣyāmi eṣaḥ sanātanaḥ vidhiḥ

17. If Indra does not cause rain for twelve years, I will perform a Vedic ritual (yajña) of worry. This is an eternal law.

Words meanings summery:

• यदि (yadi) - if (if, when)

• द्वादशवर्षाणि (dvādaśavarṣāṇi) - twelve years

• न (na) - not (not, no)

• वर्षिष्यति (varṣiṣyati) - will cause rain (will rain, will cause rain)

• वासवः (vāsavaḥ) - Indra

• चिन्तायज्ञं (cintāyajñaṁ) - a Vedic ritual (yajña) of worry (worry-Vedic ritual, ritual of anxiety)

• करिष्यामि (kariṣyāmi) - I will perform (I will do, I will make, I will perform)

• विधिः (vidhiḥ) - law, principle (rule, law, ordinance, method, destiny)

• एषः (eṣaḥ) - this (this (masculine nominative singular))

• सनातनः (sanātanaḥ) - eternal (eternal, perpetual, ancient)

Words meanings and morphology

यदि (yadi) - if (if, when)

(indeclinable)

द्वादशवर्षाणि (dvādaśavarṣāṇi) - twelve years

(noun)

Accusative, neuter, plural of dvādaśavarṣa

dvādaśavarṣa - twelve years

Compound type : dvigu (dvādaśa+varṣa)

• dvādaśa – twelve
  numeral
• varṣa – year, rain
  noun (neuter)

न (na) - not (not, no)

(indeclinable)

वर्षिष्यति (varṣiṣyati) - will cause rain (will rain, will cause rain)

(verb)

3rd person , singular, active, future (lṛṭ) of vṛṣ

root vṛṣ, future tense, 3rd person singular, active voice

Root: vṛṣ (class 1)

वासवः (vāsavaḥ) - Indra

(proper noun)

Nominative, masculine, singular of vāsava

vāsava - Indra (name of a deity)

चिन्तायज्ञं (cintāyajñaṁ) - a Vedic ritual (yajña) of worry (worry-Vedic ritual, ritual of anxiety)

(noun)

Accusative, masculine, singular of cintāyajña

cintāyajña - worry-Vedic ritual, ritual of anxiety

Compound type : tatpuruṣa (cintā+yajña)

• cintā – thought, worry, anxiety
  noun (feminine)
  Root: cit (class 10)
• yajña – Vedic ritual, devotion, worship
  noun (masculine)
  Root: yaj (class 1)

करिष्यामि (kariṣyāmi) - I will perform (I will do, I will make, I will perform)

(verb)

1st person , singular, active, future (lṛṭ) of kṛ

root kṛ, future tense, 1st person singular, active voice

Root: kṛ (class 8)

विधिः (vidhiḥ) - law, principle (rule, law, ordinance, method, destiny)

(noun)

Nominative, masculine, singular of vidhi

vidhi - rule, law, ordinance, method, destiny

Prefix: vi

Root: dhā (class 3)

एषः (eṣaḥ) - this (this (masculine nominative singular))

(pronoun)

Nominative, masculine, singular of etad

etad - this

सनातनः (sanātanaḥ) - eternal (eternal, perpetual, ancient)

(adjective)

Nominative, masculine, singular of sanātana

sanātana - eternal, perpetual, ancient

Note: Qualifies 'vidhiḥ'.