योगवासिष्ठः yogavāsiṣṭhaḥ - book-3, chapter-31, verse-16

वेतालयक्षकूश्माण्डैर्द्वन्द्वालोकनसादरैः ।
आयुधापातरक्षार्थं गृहीताद्रितटैर्वृतम् ॥ १६ ॥

vetālayakṣakūśmāṇḍairdvandvālokanasādaraiḥ ,
āyudhāpātarakṣārthaṃ gṛhītādritaṭairvṛtam 16

16. vetālayakṣakūṣmāṇḍaiḥ dvandvālokanasādaraiḥ
āyudhāpātarakṣārtham gṛhītādritaṭaiḥ vṛtam

16. vetālayakṣakūṣmāṇḍaiḥ dvandvālokanasādaraiḥ
āyudhāpātarakṣārtham gṛhītādritaṭaiḥ vṛtam

16. Furthermore, it was surrounded by Vetālas, Yakṣas, and Kūṣmāṇḍas, who were eager to watch the duels and had seized mountain slopes to protect themselves from falling weapons.

Words meanings summery:

• वेतालयक्षकूष्माण्डैः (vetālayakṣakūṣmāṇḍaiḥ) - by Vetālas, Yakṣas, and Kūṣmāṇḍas (types of demons/spirits)

• द्वन्द्वालोकनसादरैः (dvandvālokanasādaraiḥ) - (the demons) eager to watch the duels (eager to watch the duels)

• आयुधापातरक्षार्थम् (āyudhāpātarakṣārtham) - for the sake of protection from falling weapons

• गृहीताद्रितटैः (gṛhītādritaṭaiḥ) - (the demons) who had seized mountain slopes (by those who had seized mountain slopes)

• वृतम् (vṛtam) - the sky surrounded (by these beings) (surrounded, covered, enveloped)

Words meanings and morphology

वेतालयक्षकूष्माण्डैः (vetālayakṣakūṣmāṇḍaiḥ) - by Vetālas, Yakṣas, and Kūṣmāṇḍas (types of demons/spirits)

(noun)

Instrumental, masculine, plural of vetālayakṣakūṣmāṇḍa

vetālayakṣakūṣmāṇḍa - Vetāla, Yakṣa, and Kūṣmāṇḍa (types of supernatural beings)

Dvandva compound listing three types of supernatural beings.

Compound type : dvandva (vetāla+yakṣa+kūṣmāṇḍa)

• vetāla – a goblin, vampire-like demon, spirit inhabiting a corpse
  noun (masculine)
• yakṣa – a class of semi-divine beings, guardians of treasures, attendants of Kubera
  noun (masculine)
  Root: yakṣ (class 1)
• kūṣmāṇḍa – a type of demon or evil spirit, often associated with Yama
  noun (masculine)

Note: These are the agents by which the sky is surrounded.

द्वन्द्वालोकनसादरैः (dvandvālokanasādaraiḥ) - (the demons) eager to watch the duels (eager to watch the duels)

(adjective)

Instrumental, masculine, plural of dvandvālokanasādara

dvandvālokanasādara - eager to watch duels, attentive to observing duels

Compound modifying the instrumental noun phrase.

Compound type : tatpuruṣa (dvandvālokana+sādara)

• dvandva – pair, couple, duel, conflict
  noun (neuter)
• ālokana – seeing, viewing, observation
  noun (neuter)
  action noun from root `lok` (to see) with prefix `ā-`
  Prefix: ā
  Root: lok (class 10)
• sādara – respectful, attentive, eager, earnest
  adjective (masculine)
  compound of `sa` (with) + `ādara` (respect, eagerness)

Note: Modifies `vetālayakṣakūṣmāṇḍaiḥ`.

आयुधापातरक्षार्थम् (āyudhāpātarakṣārtham) - for the sake of protection from falling weapons

(indeclinable)

Compound noun used adverbially in accusative form `-artham`.

Compound type : tatpuruṣa (āyudhāpāta+rakṣā+artha)

• āyudha – weapon, implement
  noun (neuter)
  Prefix: ā
  Root: yudh (class 4)
• āpāta – falling down, descent, attack
  noun (masculine)
  action noun from root `pat` (to fall) with prefix `ā-`
  Prefix: ā
  Root: pat (class 1)
• rakṣā – protection, guarding, preservation
  noun (feminine)
  action noun from root `rakṣ`
  Root: rakṣ (class 1)
• artha – purpose, aim, object, sake
  noun (masculine)

Note: Adverbial usage (accusative of purpose).

गृहीताद्रितटैः (gṛhītādritaṭaiḥ) - (the demons) who had seized mountain slopes (by those who had seized mountain slopes)

(adjective)

Instrumental, masculine, plural of gṛhītādritaṭa

gṛhītādritaṭa - having seized mountain slopes

Bahuvrīhi compound: 'by whom mountain slopes were seized'

Compound type : bahuvrīhi (gṛhīta+adritaṭa)

• gṛhīta – seized, taken, grasped, held
  adjective (masculine)
  Past Passive Participle
  from root `grah` (to seize, take)
  Root: grah (class 9)
• adritaṭa – mountain slope, mountain side
  noun (masculine)
  compound of `adri` (mountain) + `taṭa` (slope, bank)

Note: Modifies `vetālayakṣakūṣmāṇḍaiḥ`.

वृतम् (vṛtam) - the sky surrounded (by these beings) (surrounded, covered, enveloped)

(adjective)

Accusative, neuter, singular of vṛta

vṛta - surrounded, covered, chosen, appointed

Past Passive Participle

From root `vṛ` (to cover, surround).

Root: vṛ (class 5)

Note: Modifies `nabhaḥ`.