योगवासिष्ठः yogavāsiṣṭhaḥ - book-3, chapter-50, verse-20

अयं कियद्बल इति सिन्धौ तिष्ठति हेलया ।
विदूरथोऽस्त्रमाग्नेयं तत्याजाशनिशब्दवत् ॥ २० ॥

ayaṃ kiyadbala iti sindhau tiṣṭhati helayā ,
vidūratho'stramāgneyaṃ tatyājāśaniśabdavat 20

20. ayam kiyatbalaḥ iti sindhau tiṣṭhati helayā
vidūrathaḥ astram āgneyam tatyāja aśaniśabdavat

20. ayam kiyatbalaḥ iti (saḥ) sindhau helayā tiṣṭhati,
vidūrathaḥ āgneyam astram aśaniśabdavat tatyāja

20. While (Vidūratha was) thinking, "How much strength does this one (Sindhu) possess?", he stood effortlessly (before Sindhu). Then Vidūratha unleashed a fiery weapon (āgneya astra) with a sound like a thunderbolt.

Words meanings summery:

• अयम् (ayam) - this, this one, he

• कियत्बलः (kiyatbalaḥ) - of what strength, how strong

• इति (iti) - thus, in this manner, saying, thinking

• सिन्धौ (sindhau) - in the presence of (the opponent) Sindhu (in Sindhu (the river/ocean or a person's name))

• तिष्ठति (tiṣṭhati) - stands, remains, stays, exists

• हेलया (helayā) - with ease, playfully, carelessly, effortlessly

• विदूरथः (vidūrathaḥ) - Vidūratha

• अस्त्रम् (astram) - weapon, missile

• आग्नेयम् (āgneyam) - fiery (āgneya) weapon (fiery, relating to Agni)

• तत्याज (tatyāja) - he cast, he threw, he abandoned

• अशनिशब्दवत् (aśaniśabdavat) - like the sound of a thunderbolt

Words meanings and morphology

अयम् (ayam) - this, this one, he

(pronoun)

Nominative, masculine, singular of idam

idam - this, this one, he

Note: Refers to the opponent, Sindhu.

कियत्बलः (kiyatbalaḥ) - of what strength, how strong

(adjective)

Nominative, masculine, singular of kiyatbala

kiyatbala - of what strength, how strong, having how much power

Compound type : bahuvrihi (kiyat+bala)

• kiyat – how much, how great, how many
  indeclinable
• bala – strength, power, force
  noun (neuter)

Note: Forms an interrogative phrase: 'how strong is this one?'

इति (iti) - thus, in this manner, saying, thinking

(indeclinable)

सिन्धौ (sindhau) - in the presence of (the opponent) Sindhu (in Sindhu (the river/ocean or a person's name))

(noun)

Locative, masculine, singular of sindhu

sindhu - river, ocean, Indus (river), a specific person's name (Sindhu)

Note: Refers to a specific warrior named Sindhu, or metaphorically to a challenging situation like an ocean.

तिष्ठति (tiṣṭhati) - stands, remains, stays, exists

(verb)

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

Root: √sthā (class 1)

Note: Subject is implied (Vidūratha).

हेलया (helayā) - with ease, playfully, carelessly, effortlessly

(noun)

Instrumental, feminine, singular of helā

helā - play, sport, ease, disregard, contempt

Note: Describes the manner of standing.

विदूरथः (vidūrathaḥ) - Vidūratha

(proper noun)

Nominative, masculine, singular of vidūratha

vidūratha - name of a king or warrior

Note: The subject of the second sentence.

अस्त्रम् (astram) - weapon, missile

(noun)

Accusative, neuter, singular of astra

astra - missile, weapon

Root: √as (class 4)

Note: The object of the verb 'tatyāja'.

आग्नेयम् (āgneyam) - fiery (āgneya) weapon (fiery, relating to Agni)

(adjective)

Accusative, neuter, singular of āgneya

āgneya - fiery, relating to Agni (the fire god)

from Agni + -eya (patronymic/relation suffix)

Note: Agrees with 'astram'.

तत्याज (tatyāja) - he cast, he threw, he abandoned

(verb)

3rd person , singular, active, perfect (liṭ) of tyaj

Root: √tyaj (class 1)

Note: Action performed by Vidūratha.

अशनिशब्दवत् (aśaniśabdavat) - like the sound of a thunderbolt

(adjective)

Nominative, masculine, singular of aśaniśabdavat

aśaniśabdavat - like the sound of a thunderbolt

from aśani-śabda + -vat (suffix meaning 'like', 'having')

Compound type : tatpurusha (aśani+śabda+vat)

• aśani – thunderbolt, lightning
  noun (masculine)
• śabda – sound, noise, word
  noun (masculine)
• vat – like, having, possessing
  suffix
  Primary suffix -vat

Note: Describes the sound of the weapon being cast, acting adverbially.