महाभारतः mahābhārataḥ - book-3, chapter-88, verse-21

यच्च भूतं भविष्यच्च भवच्च पुरुषर्षभ ।
नारायणः प्रभुर्विष्णुः शाश्वतः पुरुषोत्तमः ॥२१॥

21. yacca bhūtaṁ bhaviṣyacca bhavacca puruṣarṣabha ,
nārāyaṇaḥ prabhurviṣṇuḥ śāśvataḥ puruṣottamaḥ.

21. yat ca bhūtam bhaviṣyat ca bhavat ca puruṣarṣabha
nārāyaṇaḥ prabhuḥ viṣṇuḥ śāśvataḥ puruṣottamaḥ

21. O best among men (puruṣarṣabha), Nārāyaṇa, who is the Lord Viṣṇu, the eternal, and the supreme cosmic person (puruṣottama), is indeed all that exists—past, future, and present.

Words meanings summery:

• यत् (yat) - which, what (that which)

• च (ca) - and

• भूतम् (bhūtam) - the past, that which has been

• भविष्यत् (bhaviṣyat) - the future, that which will be

• च (ca) - and

• भवत् (bhavat) - the present, that which is

• च (ca) - and

• पुरुषर्षभ (puruṣarṣabha) - O best among men

• नारायणः (nārāyaṇaḥ) - Nārāyaṇa (a name of Viṣṇu)

• प्रभुः (prabhuḥ) - Lord, master

• विष्णुः (viṣṇuḥ) - Viṣṇu

• शाश्वतः (śāśvataḥ) - eternal, perpetual

• पुरुषोत्तमः (puruṣottamaḥ) - the supreme cosmic person (puruṣa), best of men

Words meanings and morphology

यत् (yat) - which, what (that which)

(pronoun)

Nominative, neuter, singular of yad

yad - which, what, who

च (ca) - and

(indeclinable)

भूतम् (bhūtam) - the past, that which has been

(noun)

Nominative, neuter, singular of bhūta

bhūta - past, existed, being, creature, element

Past Passive Participle

Derived from root 'bhū' (to be) + 'kta' suffix.

Root: bhū (class 1)

भविष्यत् (bhaviṣyat) - the future, that which will be

(noun)

Nominative, neuter, singular of bhaviṣyat

bhaviṣyat - future, about to be

Future Active Participle

Derived from root 'bhū' (to be) + 'śatṛ' (future) suffix.

Root: bhū (class 1)

च (ca) - and

(indeclinable)

भवत् (bhavat) - the present, that which is

(noun)

Nominative, neuter, singular of bhavat

bhavat - existing, being, present

Present Active Participle

Derived from root 'bhū' (to be) + 'śatṛ' suffix.

Root: bhū (class 1)

च (ca) - and

(indeclinable)

पुरुषर्षभ (puruṣarṣabha) - O best among men

(noun)

Vocative, masculine, singular of puruṣarṣabha

puruṣarṣabha - best among men, chief of men (lit. 'bull among men')

Compound type : Karmadhāraya (puruṣa+ṛṣabha)

• puruṣa – man, person, human being, the cosmic person (puruṣa)
  noun (masculine)
• ṛṣabha – bull, best, chief, excellent
  noun (masculine)

नारायणः (nārāyaṇaḥ) - Nārāyaṇa (a name of Viṣṇu)

(proper noun)

Nominative, masculine, singular of nārāyaṇa

nārāyaṇa - Nārāyaṇa (abode of men/water, a name of Viṣṇu)

प्रभुः (prabhuḥ) - Lord, master

(noun)

Nominative, masculine, singular of prabhu

prabhu - lord, master, mighty, able

विष्णुः (viṣṇuḥ) - Viṣṇu

(proper noun)

Nominative, masculine, singular of viṣṇu

viṣṇu - Viṣṇu (a major deity in Hinduism)

शाश्वतः (śāśvataḥ) - eternal, perpetual

(adjective)

Nominative, masculine, singular of śāśvata

śāśvata - eternal, perpetual, everlasting

पुरुषोत्तमः (puruṣottamaḥ) - the supreme cosmic person (puruṣa), best of men

(proper noun)

Nominative, masculine, singular of puruṣottama

puruṣottama - best of men, supreme person, Viṣṇu (puruṣa)

Compound type : Ṣaṣṭhī Tatpuruṣa (puruṣa+uttama)

• puruṣa – man, person, human being, the cosmic person (puruṣa)
  noun (masculine)
• uttama – highest, best, excellent, supreme
  adjective (masculine)