योगवासिष्ठः yogavāsiṣṭhaḥ - book-2, chapter-14, verse-51

अन्धान्धमोहसुधनं चिरं दुःखाय केवलम् ।
कृतं शिलाया हृदयं दुर्मतेश्चाविचारिणः ॥ ५१ ॥

andhāndhamohasudhanaṃ ciraṃ duḥkhāya kevalam ,
kṛtaṃ śilāyā hṛdayaṃ durmateścāvicāriṇaḥ 51

51. andha-andha-moha-sudhanam ciram duḥkhāya kevalam
kṛtam śilāyāḥ hṛdayam durmateḥ ca avicāriṇaḥ

51. durmateḥ ca avicāriṇaḥ śilāyāḥ kṛtam hṛdayam
andha-andha-moha-sudhanam kevalam ciram duḥkhāya (bhavati)

51. The heart of a foolish and thoughtless person, made as if of stone, which is merely a great fortune born of profound blind delusion (moha), leads only to prolonged suffering.

Words meanings summery:

• अन्ध-अन्ध-मोह-सुधनम् (andha-andha-moha-sudhanam) - a great fortune of profound blind delusion

• चिरम् (ciram) - prolonged (for a long time, for long)

• दुःखाय (duḥkhāya) - to suffering (for sorrow, for suffering)

• केवलम् (kevalam) - merely (only, merely, exclusively)

• कृतम् (kṛtam) - made (made, done, performed)

• शिलायाः (śilāyāḥ) - of stone, like stone (of a stone, from a stone)

• हृदयम् (hṛdayam) - heart (heart, mind, essence)

• दुर्मतेः (durmateḥ) - of a foolish person (of an evil-minded, foolish person)

• च (ca) - and (and, also)

• अविचारिणः (avicāriṇaḥ) - of a thoughtless person (of one who is thoughtless, undiscriminating)

Words meanings and morphology

अन्ध-अन्ध-मोह-सुधनम् (andha-andha-moha-sudhanam) - a great fortune of profound blind delusion

(noun)

Nominative, neuter, singular of andha-andha-moha-sudhana

andha-andha-moha-sudhana - a great fortune/wealth of deep blind delusion

Compound type : tatpurusha (andha+andha+moha+sudhana)

• andha – blind
  adjective
• andha – blind
  adjective
• moha – delusion, infatuation, error
  noun (masculine)
  Root: muh (class 4)
• sudhana – great wealth, good fortune
  noun (neuter)
  Prefix: su

चिरम् (ciram) - prolonged (for a long time, for long)

(indeclinable)

दुःखाय (duḥkhāya) - to suffering (for sorrow, for suffering)

(noun)

Dative, neuter, singular of duḥkha

duḥkha - pain, sorrow, suffering, misery

केवलम् (kevalam) - merely (only, merely, exclusively)

(indeclinable)

कृतम् (kṛtam) - made (made, done, performed)

(adjective)

Nominative, neuter, singular of kṛta

kṛta - done, made, performed; deed

past passive participle

from root kṛ (to do, make)

Root: kṛ (class 8)

Note: modifies hṛdayam.

शिलायाः (śilāyāḥ) - of stone, like stone (of a stone, from a stone)

(noun)

Genitive, feminine, singular of śilā

śilā - stone, rock

हृदयम् (hṛdayam) - heart (heart, mind, essence)

(noun)

Nominative, neuter, singular of hṛdaya

hṛdaya - heart, mind, breast, essence

दुर्मतेः (durmateḥ) - of a foolish person (of an evil-minded, foolish person)

(noun)

Genitive, masculine, singular of durmati

durmati - evil-minded, foolish, bad thought

Compound type : bahuvrihi (dus+mati)

• dus – bad, difficult, ill
  indeclinable
• mati – mind, thought, intention, intelligence
  noun (feminine)
  from root man (to think)
  Root: man (class 4)

च (ca) - and (and, also)

(indeclinable)

अविचारिणः (avicāriṇaḥ) - of a thoughtless person (of one who is thoughtless, undiscriminating)

(adjective)

Genitive, masculine, singular of avicārin

avicārin - thoughtless, undiscriminating, inconsiderate

formed with negative prefix 'a' and 'vicārin' (one who discriminates/thinks)

Compound type : tatpurusha (a+vicārin)

• a – not, un-
  indeclinable
• vicārin – discriminating, reflecting, thinking
  adjective (masculine)
  agent noun from vi+√car
  -in suffix for agent. vi is upasarga. √car is root.
  Prefix: vi
  Root: car (class 1)

Note: adjective modifying durmateḥ.