योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-39, verse-4

सर्वसंदेहदुर्ध्वान्तमिहिकामातरिश्वना ।
भाति भास्वद्धिया देशस्तेन पूर्णेन्दुनेव खम् ॥ ४ ॥

sarvasaṃdehadurdhvāntamihikāmātariśvanā ,
bhāti bhāsvaddhiyā deśastena pūrṇenduneva kham 4

4. sarvasaṃdehadurdhvāntamihikāmātariśvanā bhāti
bhāsvaddhiyā deśaḥ tena pūrṇendunā iva kham

4. tena deśaḥ bhāsvaddhiyā sarvasaṃdehadurdhvāntamihikāmātariśvanā
bhāti iva kham pūrṇendunā

4. Through him, the inner being shines with a brilliant intellect, which acts like a powerful wind dispelling the dense, misty darkness of all doubts, just as the sky shines brightly by a full moon.

Words meanings summery:

• सर्वसंदेहदुर्ध्वान्तमिहिकामातरिश्वना (sarvasaṁdehadurdhvāntamihikāmātariśvanā) - (by the intellect which is) like a powerful wind dispelling the dense, misty darkness of all doubts (by the wind that clears the mist of difficult darkness of all doubts)

• भाति (bhāti) - shines brightly (shines, appears, becomes visible)

• भास्वद्धिया (bhāsvaddhiyā) - with a brilliant intellect (as a means) (by brilliant intellect, by luminous understanding)

• देशः (deśaḥ) - the inner being, the mind, or the state of understanding (region, place, space, inner self, state)

• तेन (tena) - through him (the enlightened one mentioned in the previous verse) (by him, by that)

• पूर्णेन्दुना (pūrṇendunā) - like by a radiant full moon (by a full moon)

• इव (iva) - just as, like (like, as, as if)

• खम् (kham) - the sky (sky, atmosphere, space, emptiness)

Words meanings and morphology

सर्वसंदेहदुर्ध्वान्तमिहिकामातरिश्वना (sarvasaṁdehadurdhvāntamihikāmātariśvanā) - (by the intellect which is) like a powerful wind dispelling the dense, misty darkness of all doubts (by the wind that clears the mist of difficult darkness of all doubts)

(noun)

Instrumental, masculine, singular of sarvasaṃdehadurdhvāntamihikāmātariśvan

sarvasaṁdehadurdhvāntamihikāmātariśvan - the wind for the mist of difficult darkness of all doubts

Compound: sarva (all) + saṃdeha (doubt) + dur (bad, difficult) + dhvānta (darkness) + mihikā (mist) + mātariśvan (wind).

Compound type : tatpuruṣa (sarva+saṃdeha+dur+dhvānta+mihikā+mātariśvan)

• sarva – all, every
  pronoun
• saṃdeha – doubt, uncertainty
  noun (masculine)
  sam-√dih
  Prefix: sam
  Root: dih (class 4)
• dur – bad, difficult, hard, evil
  indeclinable
• dhvānta – darkness, gloom
  noun (neuter)
  From root dhvaṃs (to fall, perish)
  Root: dhvaṃs (class 1)
• mihikā – mist, fog, dew
  noun (feminine)
  Derived from root mih (to sprinkle, urinate)
  Root: mih (class 1)
• mātariśvan – wind, air, Vāyu
  noun (masculine)
  Lit. 'growing in the mother (space)'
  Root: śvi (class 1)

Note: Instrumental form, modifying bhāsvaddhiyā.

भाति (bhāti) - shines brightly (shines, appears, becomes visible)

(verb)

3rd person , singular, active, present (laṭ) of bhā

Present tense, Parasmaipada

Derived from root bhā (to shine).

Root: bhā (class 2)

भास्वद्धिया (bhāsvaddhiyā) - with a brilliant intellect (as a means) (by brilliant intellect, by luminous understanding)

(noun)

Instrumental, feminine, singular of bhāsvaddhī

bhāsvaddhī - brilliant intellect/understanding

Compound: bhāsvat (brilliant, shining) + dhī (intellect, understanding).

Compound type : karmadhāraya (bhāsvat+dhī)

• bhāsvat – brilliant, shining, luminous
  adjective
  Present Active Participle
  Derived from bhā (to shine) with vat suffix for possession.
  Root: bhā (class 2)
• dhī – intellect, understanding, thought, wisdom
  noun (feminine)
  From root dhyai (to meditate) or dhi (to think).
  Root: dhyai (class 1)

देशः (deśaḥ) - the inner being, the mind, or the state of understanding (region, place, space, inner self, state)

(noun)

Nominative, masculine, singular of deśa

deśa - place, region, country, point, part

From root diś (to point out, show).

Root: diś (class 6)

Note: Subject of bhāti.

तेन (tena) - through him (the enlightened one mentioned in the previous verse) (by him, by that)

(pronoun)

Instrumental, masculine, singular of tad

tad - that, he, she, it

Note: Masculine instrumental singular of tad.

पूर्णेन्दुना (pūrṇendunā) - like by a radiant full moon (by a full moon)

(noun)

Instrumental, masculine, singular of pūrṇendu

pūrṇendu - full moon

Compound: pūrṇa (full) + indu (moon).

Compound type : karmadhāraya (pūrṇa+indu)

• pūrṇa – full, complete
  adjective
  Past Passive Participle
  Derived from root pṛ (to fill).
  Root: pṛ (class 3)
• indu – moon, drop, soma
  noun (masculine)
  Derived from root und (to moisten, flow).
  Root: und (class 7)

इव (iva) - just as, like (like, as, as if)

(indeclinable)

खम् (kham) - the sky (sky, atmosphere, space, emptiness)

(noun)

Nominative, neuter, singular of kha

kha - sky, atmosphere, space, cavity, void, zero

Derived from root khan (to dig) or khyā (to be known).

Root: khan (class 1)