योगवासिष्ठः yogavāsiṣṭhaḥ - book-3, chapter-70, verse-9

सुमुखग्राह्यरूपेण श्लक्ष्णपुच्छशिखाणुना ।
तदा वैपुल्यशान्त्यर्थं परं मौनव्रतं गता ॥ ९ ॥

sumukhagrāhyarūpeṇa ślakṣṇapucchaśikhāṇunā ,
tadā vaipulyaśāntyarthaṃ paraṃ maunavrataṃ gatā 9

9. su-mukha-grāhya-rūpeṇa ślākṣṇa-puccha-śikhā-aṇunā
tadā vaipulya-śānti-artham param mauna-vratam gatā

9. tadā sā (she) vaipulya-śānti-artham param mauna-vratam
gatā su-mukha-grāhya-rūpeṇa ślākṣṇa-puccha-śikhā-aṇunā

9. Then, in order to quell her vastness, she entered into a supreme vow of silence, (manifesting) through a form easily grasped by a discerning mind and as subtle as a minute particle at the tip of a delicate tail-hair.

Words meanings summery:

• सु-मुख-ग्राह्य-रूपेण (su-mukha-grāhya-rūpeṇa) - Refers to the subtle form adopted by the entity, which is easily understood or perceived by a keen intellect. (by a form perceivable by a discerning mind/mouth)

• श्लाक्ष्ण-पुच्छ-शिखा-अणुना (ślākṣṇa-puccha-śikhā-aṇunā) - Highlights the extreme subtlety and fineness of the form adopted by the entity. (by a subtle particle at the tip of a delicate tail-hair)

• तदा (tadā) - then, at that time

• वैपुल्य-शान्ति-अर्थम् (vaipulya-śānti-artham) - Indicates the purpose of adopting the vow of silence: to reduce the entity's expansive nature. (for the sake of calming vastness/expansion)

• परम् (param) - Refers to the highest or most profound form of the vow of silence. (supreme, ultimate, excellent)

• मौन-व्रतम् (mauna-vratam) - The specific spiritual practice or discipline undertaken by the entity. (vow of silence)

• गता (gatā) - Describes the entity's action of entering or adopting the vow of silence. (attained, reached, gone to, entered)

Words meanings and morphology

सु-मुख-ग्राह्य-रूपेण (su-mukha-grāhya-rūpeṇa) - Refers to the subtle form adopted by the entity, which is easily understood or perceived by a keen intellect. (by a form perceivable by a discerning mind/mouth)

(noun)

Instrumental, neuter, singular of su-mukha-grāhya-rūpa

su-mukha-grāhya-rūpa - a form perceivable by a good face or discerning intellect

Compound formed from 'su-mukha' (good/beautiful face/mind), 'grāhya' (perceivable), and 'rūpa' (form).

Compound type : tatpurusha (su+mukha+grāhya+rūpa)

• su – good, well, excellent
  indeclinable
• mukha – face, mouth, entrance, discerning intellect
  noun (neuter)
• grāhya – to be grasped, perceivable, understandable
  adjective
  Gerundive
  Gerundive (future passive participle) of root 'grah' (to grasp, seize).
  Root: grah (class 9)
• rūpa – form, appearance, nature
  noun (neuter)

श्लाक्ष्ण-पुच्छ-शिखा-अणुना (ślākṣṇa-puccha-śikhā-aṇunā) - Highlights the extreme subtlety and fineness of the form adopted by the entity. (by a subtle particle at the tip of a delicate tail-hair)

(noun)

Instrumental, masculine, singular of ślākṣṇa-puccha-śikhā-aṇu

ślākṣṇa-puccha-śikhā-aṇu - a minute particle like the tip of a fine tail

Compound describing a subtle particle by analogy to the tip of a fine tail.

Compound type : tatpurusha (ślākṣṇa+puccha+śikhā+aṇu)

• ślākṣṇa – smooth, fine, delicate, subtle
  adjective
• puccha – tail
  noun (neuter)
• śikhā – crest, tuft, tip, flame
  noun (feminine)
• aṇu – atom, minute particle, subtle
  noun (masculine)

तदा (tadā) - then, at that time

(indeclinable)

वैपुल्य-शान्ति-अर्थम् (vaipulya-śānti-artham) - Indicates the purpose of adopting the vow of silence: to reduce the entity's expansive nature. (for the sake of calming vastness/expansion)

(indeclinable)

Compound 'vaipulya-śānti' (cessation of vastness) + 'artha' (purpose).

Compound type : tatpurusha (vaipulya+śānti+artha)

• vaipulya – vastness, extensiveness, amplitude
  noun (neuter)
  Derived from 'vipula' (vast) + suffix '-ya'.
• śānti – peace, cessation, tranquility
  noun (feminine)
  Derived from root 'śam' (to be quiet, calm).
  Root: śam (class 4)
• artha – purpose, aim, meaning, wealth
  noun (masculine)

Note: Functions adverbially to express purpose.

परम् (param) - Refers to the highest or most profound form of the vow of silence. (supreme, ultimate, excellent)

(adjective)

Accusative, neuter, singular of para

para - supreme, ultimate, highest, excellent

Note: Modifies 'mauna-vratam'.

मौन-व्रतम् (mauna-vratam) - The specific spiritual practice or discipline undertaken by the entity. (vow of silence)

(noun)

Accusative, neuter, singular of mauna-vrata

mauna-vrata - vow of silence, ascetic discipline of silence

Compound 'mauna' (silence) + 'vrata' (vow).

Compound type : tatpurusha (mauna+vrata)

• mauna – silence, taciturnity
  noun (neuter)
  Derived from 'muni' (sage, silent one).
• vrata – vow, sacred observance, religious duty
  noun (neuter)

Note: Object of the action 'gatā'.

गता (gatā) - Describes the entity's action of entering or adopting the vow of silence. (attained, reached, gone to, entered)

(adjective)

Nominative, feminine, singular of gata

gata - gone, attained, reached, arrived

Past Passive Participle

Past passive participle of root 'gam' (to go, move).

Root: gam (class 1)

Note: Agrees with the implied feminine subject.