योगवासिष्ठः yogavāsiṣṭhaḥ - book-4, chapter-15, verse-2

क्रमादाकाशमाक्रम्य निर्गत्याम्बुदकोटरैः ।
संप्रापुः सिद्धमार्गेण क्षणान्मन्दरकन्दरम् ॥ २ ॥

kramādākāśamākramya nirgatyāmbudakoṭaraiḥ ,
saṃprāpuḥ siddhamārgeṇa kṣaṇānmandarakandaram 2

2. kramāt ākāśam ākramya nirgatya ambudakoṭaraiḥ
saṃprāpuḥ siddhamārgeṇa kṣaṇāt mandarakandaram

2. kramāt ākāśam ākramya ambudakoṭaraiḥ nirgatya
siddhamārgeṇa kṣaṇāt mandarakandaram saṃprāpuḥ

2. Progressively traversing the sky and emerging from the hollows of the clouds, they quickly reached the cave of Mount Mandara by the path frequented by perfected beings (siddhas).

Words meanings summery:

• क्रमात् (kramāt) - progressively, successively, in order

• आकाशम् (ākāśam) - the sky, space

• आक्रम्य (ākramya) - having traversed, having covered, having overcome

• निर्गत्य (nirgatya) - having emerged, having come out, having departed

• अम्बुदकोटरैः (ambudakoṭaraiḥ) - from/by means of the hollows of clouds, cloud-cavities

• संप्रापुः (saṁprāpuḥ) - they reached, they obtained, they attained

• सिद्धमार्गेण (siddhamārgeṇa) - by the path of the Siddhas, by the path of perfected beings

• क्षणात् (kṣaṇāt) - in a moment, instantly, quickly

• मन्दरकन्दरम् (mandarakandaram) - the cave of Mount Mandara

Words meanings and morphology

क्रमात् (kramāt) - progressively, successively, in order

(noun)

Ablative, masculine, singular of krama

krama - step, order, succession, sequence, manner

Root: kram (class 1)

Note: Used adverbially here.

आकाशम् (ākāśam) - the sky, space

(noun)

Accusative, neuter, singular of ākāśa

ākāśa - sky, space, ether, the fifth element

आक्रम्य (ākramya) - having traversed, having covered, having overcome

(indeclinable)

Absolutive (Gerund)

Formed from root kram with prefix ā, followed by -ya suffix.

Prefix: ā

Root: kram (class 1)

निर्गत्य (nirgatya) - having emerged, having come out, having departed

(indeclinable)

Absolutive (Gerund)

Formed from root gam with prefix nir, followed by -ya suffix.

Prefix: nir

Root: gam (class 1)

अम्बुदकोटरैः (ambudakoṭaraiḥ) - from/by means of the hollows of clouds, cloud-cavities

(noun)

Instrumental, neuter, plural of ambudakoṭara

ambudakoṭara - cloud-hollow, cloud-cavity

Compound type : tatpurusha (ambuda+koṭara)

• ambuda – cloud (giver of water), rain cloud
  noun (masculine)
  Compound of ambu (water) and da (giver, from root dā 'to give').
  Root: dā (class 3)
• koṭara – hollow, cavity, hole (especially in a tree)
  noun (neuter)

संप्रापुः (saṁprāpuḥ) - they reached, they obtained, they attained

(verb)

3rd person , plural, active, perfect (Lit) of saṃ-pra-āp

Prefixes: saṃ+pra

Root: āp (class 5)

सिद्धमार्गेण (siddhamārgeṇa) - by the path of the Siddhas, by the path of perfected beings

(noun)

Instrumental, masculine, singular of siddhamārga

siddhamārga - path of the perfected ones, path of the Siddhas

Compound type : tatpurusha (siddha+mārga)

• siddha – perfected, accomplished, successful; a perfected being, adept
  adjective (masculine)
  Past Passive Participle
  From root sidh 'to accomplish, succeed'.
  Root: sidh (class 1)
• mārga – path, road, way, track
  noun (masculine)
  Root: mṛj (class 2)

क्षणात् (kṣaṇāt) - in a moment, instantly, quickly

(noun)

Ablative, masculine, singular of kṣaṇa

kṣaṇa - moment, instant, very short time

Note: Used adverbially here.

मन्दरकन्दरम् (mandarakandaram) - the cave of Mount Mandara

(noun)

Accusative, neuter, singular of mandarakandara

mandarakandara - Mandara cave

Compound type : tatpurusha (mandara+kandara)

• mandara – Mount Mandara (a mythical mountain mentioned in the Samudra manthan)
  proper noun (masculine)
• kandara – cave, grotto, cavern
  noun (neuter)