महाभारतः mahābhārataḥ - book-3, chapter-246, verse-4

अतिथिव्रती क्रियावांश्च कापोतीं वृत्तिमास्थितः ।
सत्रमिष्टीकृतं नाम समुपास्ते महातपाः ॥४॥

4. atithivratī kriyāvāṁśca kāpotīṁ vṛttimāsthitaḥ ,
satramiṣṭīkṛtaṁ nāma samupāste mahātapāḥ.

4. atithivratī kriyāvān ca kāpotīm vṛttim āsthitaḥ
satram iṣṭīkṛtam nāma samupāste mahātapāḥ

4. That great ascetic (mahātapāḥ), observing the vow of hospitality and diligent in his religious duties, has adopted a pigeon-like way of life. He practices a sacrificial session (satra) which is called 'iṣṭīkṛta' (made of offerings).

Words meanings summery:

• अतिथिव्रती (atithivratī) - one who has undertaken the vow of hospitality

• क्रियावान् (kriyāvān) - diligent in his religious duties (active, performing actions, diligent, virtuous)

• च (ca) - and, also

• कापोतीम् (kāpotīm) - pigeon-like, pertaining to a pigeon

• वृत्तिम् (vṛttim) - way of life, conduct, means of livelihood, course of action

• आस्थितः (āsthitaḥ) - adopted (a way of life) (established, adopted, resorted to, standing)

• सत्रम् (satram) - sacrificial session, offering, assembly

• इष्टीकृतम् (iṣṭīkṛtam) - considered a sacrifice, or named 'made of offerings' (made into an offering, treated as a sacrifice, performed as a sacrifice)

• नाम (nāma) - named (iṣṭīkṛta) (by name, indeed, namely)

• समुपास्ते (samupāste) - practices (a sacrificial session) (worships, attends, practices, approaches, serves)

• महातपाः (mahātapāḥ) - one of great austerity, a great ascetic

Words meanings and morphology

अतिथिव्रती (atithivratī) - one who has undertaken the vow of hospitality

(noun)

Nominative, masculine, singular of atithivratin

atithivratin - one who observes the vow of hospitality

derived from atithi (guest) + vrata (vow) + -in (suffix indicating possession)

Compound type : tatpurusha (atithi+vrata)

• atithi – guest, stranger
  noun (masculine)
• vrata – vow, sacred observance, religious practice
  noun (neuter)

क्रियावान् (kriyāvān) - diligent in his religious duties (active, performing actions, diligent, virtuous)

(adjective)

Nominative, masculine, singular of kriyāvat

kriyāvat - active, diligent, performing actions, possessing action

derived from kriyā (action, ritual) + mat/vat (suffix indicating possession)

Compound type : tatpurusha (kriyā)

• kriyā – action, deed, ritual, religious performance
  noun (feminine)

च (ca) - and, also

(indeclinable)

कापोतीम् (kāpotīm) - pigeon-like, pertaining to a pigeon

(adjective)

Accusative, feminine, singular of kāpotī

kāpotī - pigeon-like, resembling a pigeon, pertaining to a pigeon (feminine form)

derived from kapota (pigeon)

वृत्तिम् (vṛttim) - way of life, conduct, means of livelihood, course of action

(noun)

Accusative, feminine, singular of vṛtti

vṛtti - way of life, conduct, livelihood, mode of existence

from √vṛt (to exist, to be, to turn)

Root: vṛt (class 1)

आस्थितः (āsthitaḥ) - adopted (a way of life) (established, adopted, resorted to, standing)

(adjective)

Nominative, masculine, singular of āsthita

āsthita - adopted, resorted to, established, standing

Past Passive Participle

derived from the root √sthā (to stand) with the prefix ā

Prefix: ā

Root: sthā (class 1)

Note: Used here as a predicate adjective for the subject mahātapāḥ.

सत्रम् (satram) - sacrificial session, offering, assembly

(noun)

Accusative, neuter, singular of satra

satra - sacrificial session, offering, assembly, charitable distribution

इष्टीकृतम् (iṣṭīkṛtam) - considered a sacrifice, or named 'made of offerings' (made into an offering, treated as a sacrifice, performed as a sacrifice)

(adjective)

Accusative, neuter, singular of iṣṭīkṛta

iṣṭīkṛta - made into an offering, performed as a sacrifice

Past Passive Participle

Compound noun iṣṭi + PPP of √kṛ. Can function as an adjective.

Compound type : karmadhāraya (iṣṭi+kṛta)

• iṣṭi – offering, sacrifice, worship
  noun (feminine)
• kṛta – made, done, performed
  adjective (neuter)
  Past Passive Participle
  Derived from the root √kṛ
  Root: kṛ (class 8)

Note: Agreeing with satram.

नाम (nāma) - named (iṣṭīkṛta) (by name, indeed, namely)

(indeclinable)

समुपास्ते (samupāste) - practices (a sacrificial session) (worships, attends, practices, approaches, serves)

(verb)

3rd person , singular, middle, present (laṭ) of sam-upa-ās

Present tense, Atmanepada.

Prefixes: sam+upa

Root: ās (class 2)

महातपाः (mahātapāḥ) - one of great austerity, a great ascetic

(noun)

Nominative, masculine, singular of mahātapas

mahātapas - one of great austerity (tapas)

Compound of mahā (great) and tapas (austerity).

Compound type : bahuvrihi (mahā+tapas)

• mahā – great, large, extensive
  adjective
• tapas – austerity, penance, heat, spiritual fervor
  noun (neuter)
  Root: tap (class 1)

Note: The subject of the sentence.