योगवासिष्ठः yogavāsiṣṭhaḥ - book-4, chapter-21, verse-15

तन्निश्चयमुपादाय तत्रैव रसमृच्छति ।
यन्मयत्वं शरीरे तु ततो बुद्धीन्द्रियेषु च ॥ १५ ॥

tanniścayamupādāya tatraiva rasamṛcchati ,
yanmayatvaṃ śarīre tu tato buddhīndriyeṣu ca 15

15. tat niścayam upādāya tatra eva rasam ṛcchati
yanmayatvam śarīre tu tataḥ buddhīndriyeṣu ca

15. tat niścayam upādāya tatra eva rasam ṛcchati
yanmayatvam śarīre tu tataḥ ca buddhīndriyeṣu

15. Having embraced that determination, one then experiences delight (rasa) in that very thing. The state of identification with that (yanmayatva) then manifests in the body, and subsequently in the intellect and sense organs.

Words meanings summery:

• तत् (tat) - that (that, its)

• निश्चयम् (niścayam) - determination, certainty (certainty, determination, resolution)

• उपादाय (upādāya) - having embraced (having taken up, having accepted, having embraced)

• तत्र (tatra) - in that (thing/matter) (there, in that place, in that matter)

• एव (eva) - very (only, indeed, just)

• रसम् (rasam) - delight (rasa) (taste, essence, delight, emotional flavor (rasa))

• ऋच्छति (ṛcchati) - experiences, obtains (obtains, reaches, experiences, goes to)

• यन्मयत्वम् (yanmayatvam) - the state of identification with that (the state of being identified with which, composed of which)

• शरीरे (śarīre) - in the body

• तु (tu) - then, indeed (but, indeed, however)

• ततः (tataḥ) - thereafter (then, thereafter, from that)

• बुद्धीन्द्रियेषु (buddhīndriyeṣu) - in the intellect and sense organs

• च (ca) - and

Words meanings and morphology

तत् (tat) - that (that, its)

(pronoun)

Nominative, neuter, singular of tad

tad - that, it

Note: Here functions as the first part of tanniścayam compound.

निश्चयम् (niścayam) - determination, certainty (certainty, determination, resolution)

(noun)

Accusative, masculine, singular of niścaya

niścaya - certainty, determination, resolution, decision

Prefix: nis

Root: ci (class 5)

Note: Object of upādāya.

उपादाय (upādāya) - having embraced (having taken up, having accepted, having embraced)

(indeclinable)

absolutive (gerund)

Root dā (to give) with prefix upā and suffix lyaP.

Prefix: upā

Root: dā (class 3)

तत्र (tatra) - in that (thing/matter) (there, in that place, in that matter)

(indeclinable)

Derived from tad with suffix tra.

एव (eva) - very (only, indeed, just)

(indeclinable)

रसम् (rasam) - delight (rasa) (taste, essence, delight, emotional flavor (rasa))

(noun)

Accusative, masculine, singular of rasa

rasa - taste, flavor, essence, juice, emotional sentiment, delight, charm

Root: ras (class 1)

Note: Object of ṛcchati.

ऋच्छति (ṛcchati) - experiences, obtains (obtains, reaches, experiences, goes to)

(verb)

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

present tense, 3rd person singular, parasmaipada

Root ṛch or ṛcch (from ṛ + cch suffix)

Root: ṛ (class 1)

यन्मयत्वम् (yanmayatvam) - the state of identification with that (the state of being identified with which, composed of which)

(noun)

Nominative, neuter, singular of yanmayatva

yanmayatva - the state of being identified with that, composed of which

Compound of yad (which) + maya (made of, consisting of) + tva (suffix for state/nature).

Compound type : tatpuruṣa (yad+maya+tva)

• yad – which, what
  pronoun (neuter)
• maya – made of, consisting of, full of, identified with
  adjective (masculine)
  Secondary suffix mayaṭ.
• tva – -ness, -hood, state of being
  suffix (neuter)
  Abstract noun suffix.

Note: Subject of an implied verb like 'becomes' or 'manifests'.

शरीरे (śarīre) - in the body

(noun)

Locative, neuter, singular of śarīra

śarīra - body, corporeal frame

Root: śṝ (class 9)

Note: Locative of place where yanmayatvam manifests.

तु (tu) - then, indeed (but, indeed, however)

(indeclinable)

ततः (tataḥ) - thereafter (then, thereafter, from that)

(indeclinable)

Derived from tad with suffix tas.

बुद्धीन्द्रियेषु (buddhīndriyeṣu) - in the intellect and sense organs

(noun)

Locative, neuter, plural of buddhīndriya

buddhīndriya - intellect and sense organs

Compound type : dvandva (buddhi+indriya)

• buddhi – intellect, understanding, perception, reason
  noun (feminine)
  Derived from root budh (to awaken, know) with suffix ti.
  Root: budh (class 1)
• indriya – sense organ (power, faculty)
  noun (neuter)
  Related to indra.

Note: Locative of place.

च (ca) - and

(indeclinable)

Note: Connects śarīre and buddhīndriyeṣu.