महाभारतः mahābhārataḥ - book-5, chapter-113, verse-18

सोऽगच्छन्मनसेक्ष्वाकुं हर्यश्वं राजसत्तमम् ।
अयोध्यायां महावीर्यं चतुरङ्गबलान्वितम् ॥१८॥

18. so'gacchanmanasekṣvākuṁ haryaśvaṁ rājasattamam ,
ayodhyāyāṁ mahāvīryaṁ caturaṅgabalānvitam.

18. saḥ agacchat manasā ikṣvākum haryaśvam rājasattamam
ayodhyāyām mahāvīryam caturaṅgabalānvitam

18. He (Gālava) mentally approached Ikṣvāku Haryaśva, the best among kings, who was greatly valorous, and endowed with a four-limbed army, in Ayodhyā.

Words meanings summery:

• सः (saḥ) - he (Gālava) (he, that)

• अगच्छत् (agacchat) - he mentally approached (he went, he approached)

• मनसा (manasā) - mentally (by/with the mind, mentally, in thought)

• इक्ष्वाकुम् (ikṣvākum) - Ikṣvāku (Ikṣvāku (name of a king))

• हर्यश्वम् (haryaśvam) - Haryaśva (a specific king in the Ikṣvāku lineage or an epithet for Ikṣvāku) (Haryaśva (name of a king or an epithet))

• राजसत्तमम् (rājasattamam) - the best among kings (best among kings, chief of kings)

• अयोध्यायाम् (ayodhyāyām) - in Ayodhyā (in Ayodhyā (city))

• महावीर्यम् (mahāvīryam) - greatly valorous (greatly valorous, of great power, very heroic)

• चतुरङ्गबलान्वितम् (caturaṅgabalānvitam) - endowed with a four-limbed army (endowed with a four-limbed army (elephants, chariots, cavalry, infantry))

Words meanings and morphology

सः (saḥ) - he (Gālava) (he, that)

(pronoun)

Nominative, masculine, singular of tad

tad - that, he, she, it

अगच्छत् (agacchat) - he mentally approached (he went, he approached)

(verb)

3rd person , singular, active, past imperfect (Laṅ) of gam

Imperfect Tense (Laṅ)

3rd person singular, active voice, imperfect tense of root gam (1P)

Root: gam (class 1)

मनसा (manasā) - mentally (by/with the mind, mentally, in thought)

(noun)

Instrumental, neuter, singular of manas

manas - mind, intellect, thought, heart

इक्ष्वाकुम् (ikṣvākum) - Ikṣvāku (Ikṣvāku (name of a king))

(proper noun)

Accusative, masculine, singular of ikṣvāku

ikṣvāku - name of a legendary king, founder of the solar dynasty

हर्यश्वम् (haryaśvam) - Haryaśva (a specific king in the Ikṣvāku lineage or an epithet for Ikṣvāku) (Haryaśva (name of a king or an epithet))

(proper noun)

Accusative, masculine, singular of haryaśva

haryaśva - having bay horses; name of a king

Compound type : bahuvrihi (hari+aśva)

• hari – bay, reddish-brown, yellow, green
  adjective
• aśva – horse
  noun (masculine)

राजसत्तमम् (rājasattamam) - the best among kings (best among kings, chief of kings)

(adjective)

Accusative, masculine, singular of rājasattama

rājasattama - best among kings, chief of kings

From rājan (king) + sattama (superlative suffix, best)

Compound type : tatpurusha (rājan+sattama)

• rājan – king, ruler
  noun (masculine)
• sattama – best, most excellent, chief
  adjective
  Superlative suffix tama

अयोध्यायाम् (ayodhyāyām) - in Ayodhyā (in Ayodhyā (city))

(proper noun)

Locative, feminine, singular of ayodhyā

ayodhyā - Ayodhyā (name of an ancient city, capital of Kośala)

महावीर्यम् (mahāvīryam) - greatly valorous (greatly valorous, of great power, very heroic)

(adjective)

Accusative, masculine, singular of mahāvīrya

mahāvīrya - greatly valorous, of great power

Compound type : bahuvrihi (mahā+vīrya)

• mahā – great, mighty
  adjective
• vīrya – valor, strength, heroism
  noun (neuter)

चतुरङ्गबलान्वितम् (caturaṅgabalānvitam) - endowed with a four-limbed army (endowed with a four-limbed army (elephants, chariots, cavalry, infantry))

(adjective)

Accusative, masculine, singular of caturaṅgabalānvita

caturaṅgabalānvita - endowed with a four-limbed army

From caturaṅgabalā (four-limbed army) + anvita (joined with, possessed of)

Compound type : tatpurusha (caturaṅgabalā+anvita)

• caturaṅgabalā – four-limbed army (elephants, chariots, cavalry, infantry)
  noun (feminine)
  Compound: caturaṅga (four-limbed) + bala (army)
• anvita – joined, accompanied, endowed with
  adjective
  Past Passive Participle
  From root i (2P) with prefix anu + kta (ta)
  Prefix: anu
  Root: i (class 2)

Note: The full compound is 'endowed with a four-limbed army'. 'Caturaṅgabalā' is a standard term for a complete army.