महाभारतः mahābhārataḥ - book-6, chapter-83, verse-2

ततः शब्दो महानासीत्सेनयोरुभयोरपि ।
निर्गच्छमानयोः संख्ये सागरप्रतिमो महान् ॥२॥

2. tataḥ śabdo mahānāsītsenayorubhayorapi ,
nirgacchamānayoḥ saṁkhye sāgarapratimo mahān.

2. tataḥ śabdaḥ mahān āsīt senayoḥ ubhayoḥ api
nirgacchamānayoḥ saṅkhye sāgarapratimo mahān

2. tataḥ ubhayoḥ senayoḥ api saṅkhye nirgacchamānayoḥ
mahān sāgarapratimaḥ mahān śabdaḥ āsīt

2. Then a great sound, vast and ocean-like, arose from both armies as they marched out to battle.

Words meanings summery:

• ततः (tataḥ) - Indicates sequence of events. (then, from that, therefore)

• शब्दः (śabdaḥ) - The roar or din of the marching armies. (sound, noise, word)

• महान् (mahān) - Describes the intensity and volume of the sound. (great, large, mighty)

• आसीत् (āsīt) - was, existed

• सेनयोः (senayoḥ) - Refers to the armies of the Kurus and Pandavas. (of the armies, in the armies)

• उभयोः (ubhayoḥ) - Qualifies 'senayoḥ' (of the armies). (of both, in both)

• अपि (api) - Emphasizes 'both'. (also, even, too)

• निर्गच्छमानयोः (nirgacchamānayoḥ) - Describes the armies as they move. (of those going forth, of those marching out)

• सङ्ख्ये (saṅkhye) - Refers to the context of the armies' movement towards combat. (in battle, on the battlefield, in confrontation)

• सागरप्रतिमो (sāgarapratimo) - Describes the vastness and roar of the sound, like the ocean's expanse and waves. (ocean-like, resembling the ocean)

• महान् (mahān) - Reinforces the idea of the immense magnitude of the sound, emphasizing the comparison to the ocean. (great, vast, immense)

Words meanings and morphology

ततः (tataḥ) - Indicates sequence of events. (then, from that, therefore)

(indeclinable)

शब्दः (śabdaḥ) - The roar or din of the marching armies. (sound, noise, word)

(noun)

Nominative, masculine, singular of śabda

śabda - sound, noise, word

महान् (mahān) - Describes the intensity and volume of the sound. (great, large, mighty)

(adjective)

Nominative, masculine, singular of mahat

mahat - great, large, vast, mighty

आसीत् (āsīt) - was, existed

(verb)

3rd person , singular, active, past imperfect (laṅ) of as

Imperfect tense, 3rd person singular

Root: as (class 2)

सेनयोः (senayoḥ) - Refers to the armies of the Kurus and Pandavas. (of the armies, in the armies)

(noun)

Genitive, feminine, dual of senā

senā - army, host

Note: Also could be locative dual, but genitive 'of the armies' fits better for the source of the sound.

उभयोः (ubhayoḥ) - Qualifies 'senayoḥ' (of the armies). (of both, in both)

(pronoun)

Genitive, feminine, dual of ubha

ubha - both

अपि (api) - Emphasizes 'both'. (also, even, too)

(indeclinable)

निर्गच्छमानयोः (nirgacchamānayoḥ) - Describes the armies as they move. (of those going forth, of those marching out)

(adjective)

Genitive, feminine, dual of nirgacchamāna

nirgacchamāna - going forth, marching out

Present Middle Participle

Derived from nir- + √gam (to go) in the present tense, middle voice

Prefix: nir

Root: gam (class 1)

Note: Used here to qualify 'senayoḥ ubhayoḥ'.

सङ्ख्ये (saṅkhye) - Refers to the context of the armies' movement towards combat. (in battle, on the battlefield, in confrontation)

(noun)

Locative, neuter, singular of saṅkhya

saṅkhya - battle, war, confrontation, reckoning

सागरप्रतिमो (sāgarapratimo) - Describes the vastness and roar of the sound, like the ocean's expanse and waves. (ocean-like, resembling the ocean)

(adjective)

Nominative, masculine, singular of sāgarapratima

sāgarapratima - ocean-like, comparable to the ocean

Compound of sāgara (ocean) and pratima (resembling)

Compound type : tatpuruṣa (sāgara+pratima)

• sāgara – ocean, sea
  noun (masculine)
• pratima – likeness, image, resembling, comparable to
  adjective
  Prefix: prati

Note: Here agrees with 'śabdaḥ'.

महान् (mahān) - Reinforces the idea of the immense magnitude of the sound, emphasizing the comparison to the ocean. (great, vast, immense)

(adjective)

Nominative, masculine, singular of mahat

mahat - great, large, vast, mighty

Note: Adjective modifying 'śabdaḥ' again, used emphatically.