महाभारतः mahābhārataḥ - book-13, chapter-144, verse-42

षोडशानां सहस्राणां वधूनां केशवस्य ह ।
वरिष्ठा सहलोक्या च केशवस्य भविष्यसि ॥४२॥

42. ṣoḍaśānāṁ sahasrāṇāṁ vadhūnāṁ keśavasya ha ,
variṣṭhā sahalokyā ca keśavasya bhaviṣyasi.

42. ṣoḍaśānām sahasrāṇām vadhūnām keśavasya ha |
variṣṭhā saha-lokyā ca keśavasya bhaviṣyasi

42. (tvam) keśavasya ṣoḍaśānām sahasrāṇām vadhūnām variṣṭhā
bhaviṣyasi ha ca keśavasya saha-lokyā (api) bhaviṣyasi

42. “You will be the foremost among the sixteen thousand wives of Keśava, and you will share his world.”

Words meanings summery:

• षोडशानाम् (ṣoḍaśānām) - of sixteen

• सहस्राणाम् (sahasrāṇām) - of thousands

• वधूनाम् (vadhūnām) - of wives, of brides, of women

• केशवस्य (keśavasya) - of Keśava (Krishna)

• ह (ha) - indeed, certainly (emphatic particle)

• वरिष्ठा (variṣṭhā) - foremost, most excellent, best

• सह-लोक्या (saha-lokyā) - sharing the same world, co-existent in world

• च (ca) - and, also

• केशवस्य (keśavasya) - of Keśava (Krishna)

• भविष्यसि (bhaviṣyasi) - you will be

Words meanings and morphology

षोडशानाम् (ṣoḍaśānām) - of sixteen

(numeral)

Note: Agrees with sahasrāṇām.

सहस्राणाम् (sahasrāṇām) - of thousands

(noun)

Genitive, neuter, plural of sahasra

sahasra - thousand

Note: Modifies vadhūnām.

वधूनाम् (vadhūnām) - of wives, of brides, of women

(noun)

Genitive, feminine, plural of vadhū

vadhū - wife, bride, daughter-in-law, young woman

Note: Governed by variṣṭhā.

केशवस्य (keśavasya) - of Keśava (Krishna)

(proper noun)

Genitive, masculine, singular of keśava

keśava - Keśava (an epithet of Vishnu/Krishna)

Note: Possessive, 'of Keśava'.

ह (ha) - indeed, certainly (emphatic particle)

(indeclinable)

Note: Emphatic particle.

वरिष्ठा (variṣṭhā) - foremost, most excellent, best

(adjective)

Nominative, feminine, singular of variṣṭha

variṣṭha - foremost, most excellent, best (superlative of 'vara')

Superlative degree from 'vara'

Note: Predicative adjective for the implied 'you'.

सह-लोक्या (saha-lokyā) - sharing the same world, co-existent in world

(adjective)

Nominative, feminine, singular of saha-lokya

saha-lokya - sharing the same world, co-existent in world

Derived from 'saha-loka' (co-world)

Compound type : bahuvrīhi (saha+loka)

• saha – with, together with
  indeclinable
• loka – world, realm
  noun (masculine)

Note: Predicative adjective for the implied 'you' (Rukmini).

च (ca) - and, also

(indeclinable)

Note: Conjunction.

केशवस्य (keśavasya) - of Keśava (Krishna)

(proper noun)

Genitive, masculine, singular of keśava

keśava - Keśava (an epithet of Vishnu/Krishna)

Note: Possessive, 'of Keśava'.

भविष्यसि (bhaviṣyasi) - you will be

(verb)

2nd person , singular, active, future (lṛṭ) of bhū

Future tense, active voice

Root: bhū (class 1)