योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-100, verse-18

देशकालक्रियाद्रव्यवेदशास्त्रैषणाभ्रमैः ।
अबोधता तु या संवित्कदाचित्सा न नश्यति ॥ १८ ॥

deśakālakriyādravyavedaśāstraiṣaṇābhramaiḥ ,
abodhatā tu yā saṃvitkadācitsā na naśyati 18

18. deśakālakriyādravyavedaśāstraiṣaṇābhramaiḥ
abodhatā tu yā saṃvit kadācit sā na naśyati

18. But that very lack of knowledge (abodha), which is consciousness (saṃvid) itself, is never destroyed by the delusions arising from place, time, action, substance, the Vedas, the scriptures (śāstras), and worldly desires.

Words meanings summery:

• देशकालक्रियाद्रव्यवेदशास्त्रैषणाभ्रमैः (deśakālakriyādravyavedaśāstraiṣaṇābhramaiḥ) - by the errors/delusions related to place, time, action, substance, Veda, scripture, and desires

• अबोधता (abodhatā) - ignorance, lack of knowledge, unawakened state

• तु (tu) - but, however, on the other hand

• या (yā) - which, who (feminine)

• संवित् (saṁvit) - consciousness (saṃvid) (consciousness, knowledge, understanding, intellect)

• कदाचित् (kadācit) - never (with na) (sometimes, ever, at any time)

• सा (sā) - Refers to abodhatā. (she, it (feminine))

• न (na) - not, no

• नश्यति (naśyati) - perishes, is destroyed, disappears

Words meanings and morphology

देशकालक्रियाद्रव्यवेदशास्त्रैषणाभ्रमैः (deśakālakriyādravyavedaśāstraiṣaṇābhramaiḥ) - by the errors/delusions related to place, time, action, substance, Veda, scripture, and desires

(noun)

Instrumental, masculine, plural of deśakālakriyādravyavedaśāstraiṣaṇābhrama

deśakālakriyādravyavedaśāstraiṣaṇābhrama - errors or delusions concerning place, time, action, substance, Veda, scripture, and desires

A long Dvandva compound (listing items) followed by a Tatpuruṣa compound with bhrama (delusion/error).

Compound type : dvandva-tatpuruṣa (deśa+kāla+kriyā+dravya+veda+śāstra+eṣaṇā+bhrama)

• deśa – place, region, country
  noun (masculine)
• kāla – time
  noun (masculine)
• kriyā – action, activity, ritual
  noun (feminine)
  From root kṛ (to do, make).
  Root: kṛ (class 8)
• dravya – substance, material, thing
  noun (neuter)
• veda – Veda, sacred knowledge
  noun (masculine)
  From root vid (to know).
  Root: vid (class 2)
• śāstra – scripture, science, treatise, doctrine
  noun (neuter)
  From root śās (to instruct, command).
  Root: śās (class 2)
• eṣaṇā – desire, wish, search, pursuit
  noun (feminine)
  From root eṣ (to seek, desire).
  Root: eṣ (class 1)
• bhrama – error, delusion, illusion, wandering
  noun (masculine)
  From root bhram (to wander, err).
  Root: bhram (class 1)

Note: Indicates the means by which something might be destroyed (but is not).

अबोधता (abodhatā) - ignorance, lack of knowledge, unawakened state

(noun)

Nominative, feminine, singular of abodhatā

abodhatā - ignorance, lack of knowledge, unawakened state

Compound of a (not) + bodha (knowledge) + -tā (suffix for abstract noun, state of being).

Compound type : nañ-tatpuruṣa (a+bodha)

• a – not, non-, un-
  indeclinable
• bodha – knowledge, understanding, awakening
  noun (masculine)
  From root budh (to awaken, know).
  Root: budh (class 1)

Note: Subject.

तु (tu) - but, however, on the other hand

(indeclinable)

Particle used to mark a contrast or emphasis.

या (yā) - which, who (feminine)

(pronoun)

Nominative, feminine, singular of yad

yad - which, who, what

Relative pronoun.

संवित् (saṁvit) - consciousness (saṃvid) (consciousness, knowledge, understanding, intellect)

(noun)

Nominative, feminine, singular of saṃvid

saṁvid - consciousness, knowledge, understanding, intellect, awareness

From root vid (to know) with sam (together, complete).

Prefix: sam

Root: vid (class 2)

कदाचित् (kadācit) - never (with na) (sometimes, ever, at any time)

(indeclinable)

Adverb formed from kadā (when) + cit (particle).

सा (sā) - Refers to abodhatā. (she, it (feminine))

(pronoun)

Nominative, feminine, singular of tad

tad - that, this, it

Demonstrative pronoun.

न (na) - not, no

(indeclinable)

Negative particle.

नश्यति (naśyati) - perishes, is destroyed, disappears

(verb)

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

Present active 3rd singular

From root naś.

Root: naś (class 4)

Note: The subject is abodhatā / sā.