योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-23, verse-3

अहं कदाचिदाकाशकोशादवनिमागतः ।
भवत्पितामहार्थेन केनाप्युपनिमन्त्रितः ॥ ३ ॥

ahaṃ kadācidākāśakośādavanimāgataḥ ,
bhavatpitāmahārthena kenāpyupanimantritaḥ 3

3. aham kadācit ākāśakośāt avanim āgataḥ
bavatpitāmahārthena kena api upanīmantritaḥ

3. aham kadācit ākāśakośāt avanim āgataḥ
bavatpitāmahārthena kena api upanīmantritaḥ

3. Once, I came to earth from the ethereal sphere, having been invited by someone for the sake of your grandfather.

Words meanings summery:

• अहम् (aham) - I

• कदाचित् (kadācit) - once, sometimes, at some time

• आकाशकोशात् (ākāśakośāt) - from the sphere of space, from the ethereal realm

• अवनिम् (avanim) - to the earth, ground

• आगतः (āgataḥ) - having come, arrived

• बवत्पितामहार्थेन (bavatpitāmahārthena) - for the sake of your grandfather

• केन (kena) - by whom, by some, by a certain one

• अपि (api) - also, even, indeed, (with interrogative) any/some

• उपनीमन्त्रितः (upanīmantritaḥ) - invited

Words meanings and morphology

अहम् (aham) - I

(pronoun)

Nominative, singular of aham

aham - I, self

कदाचित् (kadācit) - once, sometimes, at some time

(indeclinable)

आकाशकोशात् (ākāśakośāt) - from the sphere of space, from the ethereal realm

(noun)

Ablative, masculine, singular of ākāśakośa

ākāśakośa - a sheath of space, ethereal sphere

Compound type : tatpuruṣa (ākāśa+kośa)

• ākāśa – sky, space, ether
  noun (masculine)
• kośa – sheath, case, treasury, sphere
  noun (masculine)

अवनिम् (avanim) - to the earth, ground

(noun)

Accusative, feminine, singular of avani

avani - earth, ground

आगतः (āgataḥ) - having come, arrived

(adjective)

Nominative, masculine, singular of āgata

āgata - come, arrived, approached

Past Passive Participle

Derived from root gam (to go) with prefix ā (towards)

Prefix: ā

Root: gam (class 1)

बवत्पितामहार्थेन (bavatpitāmahārthena) - for the sake of your grandfather

(noun)

Instrumental, masculine, singular of bavatpitāmahārtha

bavatpitāmahārtha - for the purpose of your grandfather

Compound type : tatpuruṣa (bavat+pitāmaha+artha)

• bavat – your, respectful 'you'
  pronoun (masculine)
• pitāmaha – grandfather
  noun (masculine)
• artha – purpose, sake, meaning, wealth
  noun (masculine)

केन (kena) - by whom, by some, by a certain one

(pronoun)

Instrumental, masculine, singular of kim

kim - who, what, which

अपि (api) - also, even, indeed, (with interrogative) any/some

(indeclinable)

उपनीमन्त्रितः (upanīmantritaḥ) - invited

(adjective)

Nominative, masculine, singular of upanīmantrita

upanīmantrita - invited, summoned

Past Passive Participle

Derived from root mantr (to advise, to consult) with prefixes upa (near) and ni (down, into).

Prefixes: upa+ni

Root: mantr (class 10)