योगवासिष्ठः yogavāsiṣṭhaḥ - book-6, chapter-81, verse-82

तुल्यकालोपलम्भासावित्थं छायातपस्थितिः ।
केवलैकोपलम्भाढ्या स्थितिर्दिवसरात्रिवत् ॥ ८२ ॥

tulyakālopalambhāsāvitthaṃ chāyātapasthitiḥ ,
kevalaikopalambhāḍhyā sthitirdivasarātrivat 82

82. tulyakālopalambhā asau ittham chāyātapasthitiḥ
kevalaikopalambhāḍhyā sthitiḥ divasarātrivat

82. ittham chāyātapasthitiḥ tulyakālopalambhā asau
kevalaikopalambhāḍhyā sthitiḥ divasarātrivat

82. Thus, that state of shadow and light is characterized by simultaneous perception. (But) the state uniquely characterized by single perception is like day and night.

Words meanings summery:

• तुल्यकालोपलम्भा (tulyakālopalambhā) - having the characteristic of being perceived at the same time (characterized by simultaneous perception)

• असौ (asau) - that (state/condition) (that (feminine/masculine, nominative singular))

• इत्थम् (ittham) - thus, in this manner

• छायातपस्थितिः (chāyātapasthitiḥ) - the condition or relationship between shadow and light (state of shadow and light)

• केवलैकोपलम्भाढ्या (kevalaikopalambhāḍhyā) - a state that is exclusively defined by the perception of one thing at a time (uniquely characterized by single perception, rich in singular apprehension)

• स्थितिः (sthitiḥ) - state, condition, existence

• दिवसरात्रिवत् (divasarātrivat) - like the sequential nature of day and night (where one is present, the other absent) (like day and night)

Words meanings and morphology

तुल्यकालोपलम्भा (tulyakālopalambhā) - having the characteristic of being perceived at the same time (characterized by simultaneous perception)

(adjective)

Nominative, feminine, singular of tulyakālopalambha

tulyakālopalambha - simultaneous perception

Compound type : tatpurusha (tulya+kāla+upalambha)

• tulya – equal, similar
  adjective (masculine)
• kāla – time
  noun (masculine)
• upalambha – perception, apprehension, acquisition
  noun (masculine)
  Derived from root labh with upasarga upa
  Prefix: upa
  Root: labh (class 1)

असौ (asau) - that (state/condition) (that (feminine/masculine, nominative singular))

(pronoun)

Nominative, feminine, singular of adas

adas - that, yonder

इत्थम् (ittham) - thus, in this manner

(indeclinable)

छायातपस्थितिः (chāyātapasthitiḥ) - the condition or relationship between shadow and light (state of shadow and light)

(noun)

Nominative, feminine, singular of chāyātapasthiti

chāyātapasthiti - the state of shadow and light

Compound type : tatpurusha (chāyā+ātapa+sthiti)

• chāyā – shadow, shade
  noun (feminine)
• ātapa – sunlight, heat
  noun (masculine)
  Derived from root tap with upasarga ā
  Prefix: ā
  Root: tap (class 1)
• sthiti – state, condition, existence
  noun (feminine)
  Derived from root sthā
  Root: sthā (class 1)

केवलैकोपलम्भाढ्या (kevalaikopalambhāḍhyā) - a state that is exclusively defined by the perception of one thing at a time (uniquely characterized by single perception, rich in singular apprehension)

(adjective)

Nominative, feminine, singular of kevalaikopalambhāḍhya

kevalaikopalambhāḍhya - exclusively possessing single perception, rich in sole apprehension

Compound type : bahuvrīhi (kevala+eka+upalambha+āḍhya)

• kevala – sole, unique, mere, absolute
  adjective (masculine)
• eka – one, single
  adjective (masculine)
• upalambha – perception, apprehension
  noun (masculine)
  Derived from root labh with upasarga upa
  Prefix: upa
  Root: labh (class 1)
• āḍhya – rich in, endowed with, prosperous
  adjective (masculine)

स्थितिः (sthitiḥ) - state, condition, existence

(noun)

Nominative, feminine, singular of sthiti

sthiti - standing, position, state, condition, existence, firmness

Derived from root sthā

Root: sthā (class 1)

दिवसरात्रिवत् (divasarātrivat) - like the sequential nature of day and night (where one is present, the other absent) (like day and night)

(indeclinable)

Suffix 'vat' appended to a dvandva compound.

Compound type : dvandva (divasa+rātri)

• divasa – day
  noun (masculine)
• rātri – night
  noun (feminine)