योगवासिष्ठः yogavāsiṣṭhaḥ - book-3, chapter-122, verse-10

अथ तानववशादसत्ये
भावनातानवमभ्यस्यति ॥ १० ॥

atha tānavavaśādasatye
bhāvanātānavamabhyasyati 10

10. atha tānavavashāt asatye
bhāvanātānavam abhyasyati

10. atha tānavavashāt asatye
bhāvanātānavam abhyasyati

10. Now, by the power of attenuation, one cultivates the attenuation of mental constructs (bhāvanā-tānava) regarding the unreal.

Words meanings summery:

• अथ (atha) - introduces a new topic or a subsequent step (now, then, moreover, further)

• तानववस्हात् (tānavavashāt) - as a consequence or result of the subtlety (attenuation) achieved earlier (by the power of attenuation, due to subtlety)

• असत्ये (asatye) - referring to mental objects or perceptions that are not ultimately real or true (in the unreal, in falsehood, concerning the non-existent)

• भावनातानवम् (bhāvanātānavam) - the practice of making one's mental images, concepts, or meditations subtle or weak (attenuation of mental constructs, subtlety of contemplation)

• अभ्यस्यति (abhyasyati) - performs the spiritual exercise of attenuating mental constructs (practices, cultivates, studies, repeats)

Words meanings and morphology

अथ (atha) - introduces a new topic or a subsequent step (now, then, moreover, further)

(indeclinable)

तानववस्हात् (tānavavashāt) - as a consequence or result of the subtlety (attenuation) achieved earlier (by the power of attenuation, due to subtlety)

(noun)

Ablative, masculine, singular of tānavavaśa

tānavavaśa - power of attenuation/subtlety

Compound type : tatpuruṣa (tānava+vaśa)

• tānava – attenuation, subtlety, thinness, slenderness
  noun (neuter)
  Derived from tanu with suffix aṇ.
  Root: tan (class 8)
• vaśa – power, control, will, influence
  noun (masculine)
  Root: vaś (class 10)

Note: Ablative case indicating cause.

असत्ये (asatye) - referring to mental objects or perceptions that are not ultimately real or true (in the unreal, in falsehood, concerning the non-existent)

(noun)

Locative, neuter, singular of asatya

asatya - unreal, false, untrue, non-existent

Compound type : nañ-tatpuruṣa (a+satya)

• a – not, non-, un-
  indeclinable
• satya – true, real, truthful, truth, reality
  adjective (neuter)
  Root: as (class 2)

Note: Locative of reference/object of practice.

भावनातानवम् (bhāvanātānavam) - the practice of making one's mental images, concepts, or meditations subtle or weak (attenuation of mental constructs, subtlety of contemplation)

(noun)

Accusative, neuter, singular of bhāvanātānava

bhāvanātānava - attenuation of mental constructs/impressions/contemplation

Compound type : tatpuruṣa (bhāvanā+tānava)

• bhāvanā – contemplation, meditation, mental image, construct, imagination, feeling
  noun (feminine)
  Root: bhū (class 1)
• tānava – attenuation, subtlety, thinness, slenderness
  noun (neuter)
  Derived from tanu with suffix aṇ.
  Root: tan (class 8)

Note: Object of abhyasyati.

अभ्यस्यति (abhyasyati) - performs the spiritual exercise of attenuating mental constructs (practices, cultivates, studies, repeats)

(verb)

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

present active

From abhi-√as (to throw, to apply oneself to)

Prefix: abhi

Root: as (class 4)

Note: Implied subject is 'one' or 'the yogi'.