योगवासिष्ठः yogavāsiṣṭhaḥ - book-4, chapter-7, verse-15

भूलोकस्यान्धतमसा लोकालोकतटो यथा ।
लज्जान्धकारतीक्ष्णांशौ तस्मिंस्तिमिरमण्डले ॥ १५ ॥

bhūlokasyāndhatamasā lokālokataṭo yathā ,
lajjāndhakāratīkṣṇāṃśau tasmiṃstimiramaṇḍale 15

15. bhūlokasya andhatamasā lokālokataṭaḥ yathā
lajjāndhakāratīkṣṇāṃśau tasmin timiramaṇḍale

15. (asau deśaḥ) bhūlokasya andhatamasā,
lokālokataṭaḥ yathā,
(babhūva).
tasmin lajjāndhakāratīkṣṇāṃśau timiramaṇḍale

15. The region (of Svarga) became filled with deep darkness, like the shore of the Lokāloka mountain (is filled) with the deep darkness of the terrestrial world (Bhūloka). In that sphere of darkness, which was sharply dark with the shame-inducing gloom...

Words meanings summery:

• भूलोकस्य (bhūlokasya) - of the terrestrial world (Bhūloka) (of the terrestrial world, of the earth world)

• अन्धतमसा (andhatamasā) - with deep darkness (with deep darkness, with blinding darkness)

• लोकालोकतटः (lokālokataṭaḥ) - the shore of the Lokāloka mountain (the shore of Lokāloka mountain)

• यथा (yathā) - just as (as, just as, in which way)

• लज्जान्धकारतीक्ष्णांशौ (lajjāndhakāratīkṣṇāṁśau) - sharply dark with the gloom of shame (in which the rays of shame-darkness were sharp/intense; sharply dark with the gloom of shame)

• तस्मिन् (tasmin) - in that (in that, upon that (masculine/neuter))

• तिमिरमण्डले (timiramaṇḍale) - in that sphere of darkness (in the sphere of darkness, in the dark circle)

Words meanings and morphology

भूलोकस्य (bhūlokasya) - of the terrestrial world (Bhūloka) (of the terrestrial world, of the earth world)

(noun)

Genitive, masculine, singular of bhūloka

bhūloka - the terrestrial world, earth; one of the seven worlds

Compound of bhū (earth) + loka (world)

Compound type : tatpuruṣa (bhū+loka)

• bhū – earth, ground, land
  noun (feminine)
  Root: bhū (class 1)
• loka – world, people, region
  noun (masculine)
  From root lok (to see)
  Root: lok (class 10)

Note: Possessive, referring to the darkness

अन्धतमसा (andhatamasā) - with deep darkness (with deep darkness, with blinding darkness)

(noun)

Instrumental, neuter, singular of andhatamas

andhatamas - blinding darkness, profound darkness, utter gloom

Compound of andha (blind) + tamas (darkness)

Compound type : karmadhāraya (andha+tamas)

• andha – blind, dark
  adjective (neuter)
  Root: andh (class 1)
• tamas – darkness, gloom; ignorance
  noun (neuter)
  Root: tam (class 4)

Note: Indicates the means by which the region is filled with darkness

लोकालोकतटः (lokālokataṭaḥ) - the shore of the Lokāloka mountain (the shore of Lokāloka mountain)

(noun)

Nominative, masculine, singular of lokālokataṭa

lokālokataṭa - the shore of the Lokāloka mountain (a mythical mountain range that separates the visible world from the region of darkness)

Compound of lokāloka (Lokāloka mountain) + taṭa (shore, bank)

Compound type : tatpuruṣa (lokāloka+taṭa)

• lokāloka – Lokāloka mountain (a mythical mountain range separating the world of light from that of darkness)
  proper noun (masculine)
  Compound: loka (world) + aloka (non-world/darkness)
• taṭa – shore, bank, slope, edge
  noun (masculine)
  Root: taṭ (class 1)

Note: Part of the simile yathā

यथा (yathā) - just as (as, just as, in which way)

(indeclinable)

Adverb of comparison

Note: Introduces the comparison

लज्जान्धकारतीक्ष्णांशौ (lajjāndhakāratīkṣṇāṁśau) - sharply dark with the gloom of shame (in which the rays of shame-darkness were sharp/intense; sharply dark with the gloom of shame)

(adjective)

Locative, masculine, singular of lajjāndhakāratīkṣṇāṃśu

lajjāndhakāratīkṣṇāṁśu - having sharp rays of the darkness of shame; intensely dark due to shame-inducing gloom

Compound. lajjā (shame) + andhakāra (darkness) + tīkṣṇa (sharp, intense) + aṃśu (ray). Metaphorically, shame is so dark, its darkness has sharp "rays"

Compound type : bahuvrīhi (lajjā+andhakāra+tīkṣṇa+aṃśu)

• lajjā – shame, modesty, bashfulness
  noun (feminine)
  From root lajj (to be ashamed)
  Root: lajj (class 1)
• andhakāra – darkness, gloom
  noun (masculine)
  From andha (blind) + kāra (maker)
  Root: kṛ (class 8)
• tīkṣṇa – sharp, keen, intense, fierce
  adjective (masculine)
  From root tij (to sharpen)
  Root: tij (class 6)
• aṃśu – ray, beam, thread
  noun (masculine)

Note: Modifies timiramaṇḍale

तस्मिन् (tasmin) - in that (in that, upon that (masculine/neuter))

(pronoun)

Locative, masculine, singular of tad

tad - that, he, she, it

Demonstrative pronoun

Note: Modifies timiramaṇḍale

तिमिरमण्डले (timiramaṇḍale) - in that sphere of darkness (in the sphere of darkness, in the dark circle)

(noun)

Locative, neuter, singular of timiramaṇḍala

timiramaṇḍala - sphere of darkness, dark region

Compound of timira (darkness) + maṇḍala (circle, sphere, region)

Compound type : tatpuruṣa (timira+maṇḍala)

• timira – darkness, gloom
  noun (neuter)
  From root tim (to be dark)
  Root: tim (class 4)
• maṇḍala – circle, disc, sphere, region, orb
  noun (neuter)
  Root: maṇḍ (class 1)

Note: Locative indicating location