वाल्मीकि-रामायणम् vālmīki-rāmāyaṇam - book-4, chapter-16, verse-23

तौ भीमबलविक्रान्तौ सुपर्णसमवेगिनौ ।
प्रवृद्धौ घोरवपुषौ चन्द्रसूर्याविवाम्बरे ॥२३॥

23. tau bhīmabalavikrāntau suparṇasamaveginau ,
pravṛddhau ghoravapuṣau candrasūryāvivāmbare.

23. tau bhīmabala-vikrāntau suparṇa-sama-veginau
pravṛddhau ghora-vapuṣau candra-sūryau iva ambare

23. tau bhīmabala-vikrāntau suparṇa-sama-veginau
pravṛddhau ghora-vapuṣau ambare candra-sūryau iva

23. Those two, formidable in strength and valor, swift like Garuḍa (suparṇa), and grown immense with terrifying forms, were like the sun and moon in the sky.

Words meanings summery:

• तौ (tau) - those two

• भीमबल-विक्रान्तौ (bhīmabala-vikrāntau) - formidable in strength and valor, of terrible might and prowess

• सुपर्ण-सम-वेगिनौ (suparṇa-sama-veginau) - swift like Garuḍa, having speed equal to Garuḍa

• प्रवृद्धौ (pravṛddhau) - greatly grown, developed, immense

• घोर-वपुषौ (ghora-vapuṣau) - of terrifying body, having dreadful forms

• चन्द्र-सूर्यौ (candra-sūryau) - the moon and the sun

• इव (iva) - like, as

• अम्बरे (ambare) - in the sky, in the atmosphere

Words meanings and morphology

तौ (tau) - those two

(pronoun)

Nominative, masculine, dual of tad

tad - that, those

भीमबल-विक्रान्तौ (bhīmabala-vikrāntau) - formidable in strength and valor, of terrible might and prowess

(adjective)

Nominative, masculine, dual of bhīmabala-vikrānta

bhīmabala-vikrānta - whose strength and valor are formidable/terrible

Compound type : bahuvrihi (bhīmabala+vikrānta)

• bhīmabala – formidable strength, terrible might
  noun (neuter)
• vikrānta – valorous, mighty, valiant, prowess
  adjective (masculine)
  Past Passive Participle
  Derived from root kram with prefix vi
  Prefix: vi
  Root: kram

सुपर्ण-सम-वेगिनौ (suparṇa-sama-veginau) - swift like Garuḍa, having speed equal to Garuḍa

(adjective)

Nominative, masculine, dual of suparṇa-sama-vegin

suparṇa-sama-vegin - having speed equal to Garuḍa/a beautiful-winged bird

Compound type : bahuvrihi (suparṇa+sama+vegin)

• suparṇa – Garuḍa (mythical eagle), having beautiful wings, a bird
  proper noun (masculine)
• sama – equal, similar, like
  adjective (masculine)
• vegin – swift, fast, quick, having speed
  adjective (masculine)

प्रवृद्धौ (pravṛddhau) - greatly grown, developed, immense

(adjective)

Nominative, masculine, dual of pravṛddha

pravṛddha - greatly increased, developed, grown, large

Past Passive Participle

Derived from root vṛdh with prefix pra

Prefix: pra

Root: vṛdh

घोर-वपुषौ (ghora-vapuṣau) - of terrifying body, having dreadful forms

(adjective)

Nominative, masculine, dual of ghora-vapus

ghora-vapus - having a terrifying body/form

Compound type : bahuvrihi (ghora+vapus)

• ghora – terrifying, dreadful, terrible
  adjective (masculine)
• vapus – body, form, figure
  noun (neuter)

चन्द्र-सूर्यौ (candra-sūryau) - the moon and the sun

(noun)

Nominative, masculine, dual of candra-sūrya

candra-sūrya - the moon and the sun

Compound type : dvandva (candra+sūrya)

• candra – moon
  noun (masculine)
• sūrya – sun
  noun (masculine)

इव (iva) - like, as

(indeclinable)

अम्बरे (ambare) - in the sky, in the atmosphere

(noun)

Locative, neuter, singular of ambara

ambara - sky, atmosphere, clothing