योगवासिष्ठः yogavāsiṣṭhaḥ - book-6, chapter-127, verse-21

सुशीतलोदकनदीं विदित्वाथ विगाह्य ताम् ।
बहिर्भ्रान्तिनिदाघास्ते निर्यान्तु कलितासुखम् ॥ २१ ॥

suśītalodakanadīṃ viditvātha vigāhya tām ,
bahirbhrāntinidāghāste niryāntu kalitāsukham 21

21. suśītalodakanadīm viditvā atha vigāhya tām
bahis bhrāntinidāghāḥ te niryāntu kalitāsukham

21. tām suśītalodakanadīm viditvā atha vigāhya te
bahis bhrāntinidāghāḥ kalitāsukham niryāntu

21. Once one has understood and then entered that river of very cool water, let the intense heat of external delusions, which is accompanied by unhappiness, depart.

Words meanings summery:

• सुशीतलोदकनदीम् (suśītalodakanadīm) - a river of very cool water

• विदित्वा (viditvā) - having known, having understood

• अथ (atha) - then, thereafter, moreover

• विगाह्य (vigāhya) - having plunged into, having entered

• ताम् (tām) - that (river) (that, her, it)

• बहिस् (bahis) - outside, external

• भ्रान्तिनिदाघाः (bhrāntinidāghāḥ) - delusion-born sufferings, heat of delusion

• ते (te) - (those sufferings) (those)

• निर्यान्तु (niryāntu) - let them go forth, let them exit, let them depart

• कलितासुखम् (kalitāsukham) - describing the nature of the departing torments (accompanied by unhappiness, producing misery)

Words meanings and morphology

सुशीतलोदकनदीम् (suśītalodakanadīm) - a river of very cool water

(noun)

Accusative, feminine, singular of suśītalodakanadī

suśītalodakanadī - a river having very cool water

Compound type : Tatpuruṣa (suśītalodaka+nadī)

• suśītalodaka – very cool water
  noun (neuter)
• nadī – river
  noun (feminine)

विदित्वा (viditvā) - having known, having understood

(indeclinable)

Absolutive (Gerund)

Derived from root 'vid' with suffix '-tvā'

Root: vid (class 2)

अथ (atha) - then, thereafter, moreover

(indeclinable)

विगाह्य (vigāhya) - having plunged into, having entered

(indeclinable)

Absolutive (Gerund) with prefix

Derived from root 'gah' with prefix 'vi-' and suffix '-ya'

Prefix: vi

Root: gah (class 1)

ताम् (tām) - that (river) (that, her, it)

(pronoun)

Accusative, feminine, singular of tad

tad - that, this, it

बहिस् (bahis) - outside, external

(indeclinable)

भ्रान्तिनिदाघाः (bhrāntinidāghāḥ) - delusion-born sufferings, heat of delusion

(noun)

Nominative, masculine, plural of bhrāntinidāgha

bhrāntinidāgha - delusion-born suffering, heat of delusion

Compound type : Tatpuruṣa (bhrānti+nidāgha)

• bhrānti – delusion, error, confusion
  noun (feminine)
• nidāgha – summer heat, suffering, torment
  noun (masculine)

ते (te) - (those sufferings) (those)

(pronoun)

Nominative, masculine, plural of tad

tad - that, this, it

निर्यान्तु (niryāntu) - let them go forth, let them exit, let them depart

(verb)

3rd person , plural, active, imperative (loṭ) of niryāntu

Imperative, 3rd person plural

Derived from root 'yā' with prefix 'nir-'

Prefix: nis

Root: yā (class 2)

कलितासुखम् (kalitāsukham) - describing the nature of the departing torments (accompanied by unhappiness, producing misery)

(indeclinable)

Compound type : Tatpuruṣa (kalita+asukha)

• kalita – joined, produced, considered, furnished with
  adjective
  Past Passive Participle
  Derived from root 'kal' (to count, hold, possess) with suffix '-ita'
  Root: kal (class 1)
• asukha – unhappiness, misery, sorrow
  noun (neuter)
  Prefix: a

Note: This neuter accusative singular form functions adverbially.