योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-73, verse-6

तस्य नाशे महानाशे महाप्रलयनामनि ।
ब्रह्मोपेन्द्रमरुद्रुद्रमहेन्द्रपरिणामिनि ॥ ६ ॥

tasya nāśe mahānāśe mahāpralayanāmani ,
brahmopendramarudrudramahendrapariṇāmini 6

6. tasya nāśe mahānāśe mahāpralayanāmani
brahmopendramarudrudramahendrapariṇāmini

6. tasya mahānāśe mahāpralayanāmani
brahmopendramarudrudramahendrapariṇāmini (sati) [jagate]

6. At its ultimate destruction, called the Great Dissolution (mahāpralaya), even when Brahmā, Upendra, Marut, Rudra, and Mahendra undergo transformation.

Words meanings summery:

• तस्य (tasya) - its (referring to the world from the previous verse) (of that, its)

• नाशे (nāśe) - at its destruction (in destruction, at ruin)

• महानाशे (mahānāśe) - at the great destruction (in the great destruction)

• महाप्रलयनामनि (mahāpralayanāmani) - named the Great Dissolution (mahāpralaya) (by the name of Mahāpralaya (Great Dissolution))

• ब्रह्मोपेन्द्रमरुद्रुद्रमहेन्द्रपरिणामिनि (brahmopendramarudrudramahendrapariṇāmini) - when Brahmā, Upendra, Marut, Rudra, and Mahendra undergo transformation (in which Brahmā, Upendra, Marut, Rudra, and Mahendra undergo transformation/cessation)

Words meanings and morphology

तस्य (tasya) - its (referring to the world from the previous verse) (of that, its)

(pronoun)

Genitive, neuter, singular of tad

tad - that, he, she, it

Note: Refers to jagat.

नाशे (nāśe) - at its destruction (in destruction, at ruin)

(noun)

Locative, masculine, singular of nāśa

nāśa - destruction, ruin, loss, disappearance

Derived from √naś (to perish)

Root: √naś (class 4)

Note: Indicates the time or circumstance of destruction.

महानाशे (mahānāśe) - at the great destruction (in the great destruction)

(noun)

Locative, masculine, singular of mahānāśa

mahānāśa - great destruction, ultimate destruction

Karmadhāraya compound of mahā (great) and nāśa (destruction)

Compound type : karmadhāraya (mahā+nāśa)

• mahā – great, large, mighty
  adjective (feminine)
  Feminine stem of mahat.
• nāśa – destruction, ruin, loss
  noun (masculine)
  Derived from √naś
  Root: √naś (class 4)

Note: Specifies the type of nāśa.

महाप्रलयनामनि (mahāpralayanāmani) - named the Great Dissolution (mahāpralaya) (by the name of Mahāpralaya (Great Dissolution))

(adjective)

Locative, masculine, singular of mahāpralayanāman

mahāpralayanāman - having the name Great Dissolution

Bahuvrīhi compound: mahāpralaya (Great Dissolution) + nāman (name)

Compound type : bahuvrīhi (mahāpralaya+nāman)

• mahāpralaya – great dissolution, final dissolution
  noun (masculine)
  Karmadhāraya compound: mahā (great) + pralaya (dissolution)
  Prefix: pra
  Root: √lī (class 4)
• nāman – name, appellation
  noun (neuter)

Note: Modifies mahānāśe.

ब्रह्मोपेन्द्रमरुद्रुद्रमहेन्द्रपरिणामिनि (brahmopendramarudrudramahendrapariṇāmini) - when Brahmā, Upendra, Marut, Rudra, and Mahendra undergo transformation (in which Brahmā, Upendra, Marut, Rudra, and Mahendra undergo transformation/cessation)

(adjective)

Locative, masculine, singular of brahmopendramarudrudramahendrapariṇāmin

brahmopendramarudrudramahendrapariṇāmin - that in which Brahmā, Upendra, Marut, Rudra, and Mahendra transform/decay

Bahuvrīhi compound: brahmopendra-marudrudra-mahendra (dvandva list of deities) + pariṇāmin (undergoing transformation)

Compound type : bahuvrīhi (brahmopendra+marudrudra+mahendra+pariṇāmin)

• brahmopendra – Brahmā and Upendra (Viṣṇu)
  noun (masculine)
  Dvandva compound of brahman and upendra
• marudrudra – Maruts and Rudra (wind-gods and Śiva)
  noun (masculine)
  Dvandva compound of marut and rudra
• mahendra – Great Indra
  noun (masculine)
  Karmadhāraya compound of mahā (great) and indra (king of gods)
• pariṇāmin – undergoing change/transformation/decay, mutable
  adjective (masculine/feminine/neuter)
  Derived from pari-√ṇam (to change, ripen, transform) with suffix in (ṇini)
  Prefix: pari
  Root: √nam (class 1)

Note: Modifies mahānāśe.