योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-141, verse-6

ज्वालासंध्याभ्रनिवहैर्वृहदग्निनदीशतः ।
शैलद्विगुणभूखण्डदानवामरपत्तनः ॥ ६ ॥

jvālāsaṃdhyābhranivahairvṛhadagninadīśataḥ ,
śailadviguṇabhūkhaṇḍadānavāmarapattanaḥ 6

6. jvālāsandhyābhranivahaiḥ bṛhadagninadīśataḥ
śailadviguṇabhūkhaṇḍadānavāmarapattanaḥ

6. (saḥ mārutaḥ) jvālāsandhyābhranivahaiḥ,
bṛhadagninadīśataḥ,
śailadviguṇabhūkhaṇḍadānavāmarapattanaḥ (āyayau).

6. Accompanied by masses of flame-like twilight clouds, it manifested as hundreds of great rivers of fire. The cities of Dānavas and Amaras, due to its power, appeared as mountain-sized, doubled fragments of the earth.

Words meanings summery:

• ज्वालासन्ध्याभ्रनिवहैः (jvālāsandhyābhranivahaiḥ) - by masses of flame-like twilight clouds

• बृहदग्निनदीशतः (bṛhadagninadīśataḥ) - referring to the wind (characterized by hundreds of great rivers of fire)

• शैलद्विगुणभूखण्डदानवामरपत्तनः (śailadviguṇabhūkhaṇḍadānavāmarapattanaḥ) - referring to the wind and its destructive power (whose cities of Dānavas and Amaras are doubled mountain-like earth-fragments)

Words meanings and morphology

ज्वालासन्ध्याभ्रनिवहैः (jvālāsandhyābhranivahaiḥ) - by masses of flame-like twilight clouds

(noun)

Instrumental, masculine, plural of jvālāsandhyābhranivaha

jvālāsandhyābhranivaha - mass of flame-like twilight clouds

Compound type : tatpurusha (jvālā+sandhyā+abhra+nivaha)

• jvālā – flame, blaze
  noun (feminine)
• sandhyā – twilight, evening, juncture
  noun (feminine)
• abhra – cloud, sky
  noun (neuter)
• nivaha – multitude, mass, collection
  noun (masculine)
  Prefix: ni
  Root: vah (class 1)

बृहदग्निनदीशतः (bṛhadagninadīśataḥ) - referring to the wind (characterized by hundreds of great rivers of fire)

(adjective)

Nominative, masculine, singular of bṛhadagninadīśata

bṛhadagninadīśata - having hundreds of great rivers of fire

Compound type : bahuvrihi (bṛhat+agni+nadī+śata)

• bṛhat – great, large, mighty
  adjective (neuter)
• agni – fire
  noun (masculine)
  Root: ag (class 1)
• nadī – river
  noun (feminine)
• śata – hundred
  noun (neuter)

शैलद्विगुणभूखण्डदानवामरपत्तनः (śailadviguṇabhūkhaṇḍadānavāmarapattanaḥ) - referring to the wind and its destructive power (whose cities of Dānavas and Amaras are doubled mountain-like earth-fragments)

(adjective)

Nominative, masculine, singular of śailadviguṇabhūkhaṇḍadānavāmarapattana

śailadviguṇabhūkhaṇḍadānavāmarapattana - whose cities of Dānavas and Amaras are mountain-sized, doubled earth-fragments

Compound type : bahuvrihi (śaila+dviguṇa+bhūkhaṇḍa+dānava+amara+pattana)

• śaila – mountain, rock
  noun (masculine)
• dviguṇa – doubled, twofold
  adjective (masculine)
  Prefix: dvi
  Root: guṇ (class 10)
• bhūkhaṇḍa – earth fragment, piece of land
  noun (neuter)
• dānava – demon, son of Danu
  proper noun (masculine)
• amara – immortal, god
  noun (masculine)
• pattana – city, town
  noun (neuter)