योगवासिष्ठः yogavāsiṣṭhaḥ - book-2, chapter-11, verse-18

राजविद्या राजगुह्यमध्यात्मज्ञानमुत्तमम् ।
ज्ञात्वा राघव राजानः परां निर्दुःखतां गताः ॥ १८ ॥

rājavidyā rājaguhyamadhyātmajñānamuttamam ,
jñātvā rāghava rājānaḥ parāṃ nirduḥkhatāṃ gatāḥ 18

18. rājavāda rājaguhyam adhyātmajñānam uttamam
jñātvā rāghava rājānaḥ parām nirdulkatām gatāḥ

18. rāghava rājānaḥ rājavāda rājaguhyam uttamam
adhyātmajñānam jñātvā parām nirdulkatām gatāḥ

18. O Rāghava, having understood this royal science, this royal secret, which is the supreme knowledge of the self (adhyātmajñāna), kings attained the highest state of freedom from sorrow.

Words meanings summery:

• राजवाद (rājavāda) - royal science, royal knowledge

• राजगुह्यम् (rājaguhyam) - royal secret, king's secret

• अध्यात्मज्ञानम् (adhyātmajñānam) - knowledge of the self (ātman) or spirit, spiritual knowledge

• उत्तमम् (uttamam) - supreme, best, excellent

• ज्ञात्वा (jñātvā) - having known, having understood

• राघव (rāghava) - O descendant of Raghu, O Rāma

• राजानः (rājānaḥ) - kings

• पराम् (parām) - supreme, highest

• निर्दुल्कताम् (nirdulkatām) - freedom from suffering/sorrow, state of being without sorrow

• गताः (gatāḥ) - attained, gone to, reached

Words meanings and morphology

राजवाद (rājavāda) - royal science, royal knowledge

(noun)

Nominative, feminine, singular of rājavāda

rājavāda - royal knowledge, king's science

Compound type : tatpurusha (rājan+vidyā)

• rājan – king, ruler
  noun (masculine)
• vidyā – knowledge, learning, science, discipline
  noun (feminine)
  Root: vid (class 2)

राजगुह्यम् (rājaguhyam) - royal secret, king's secret

(noun)

Nominative, neuter, singular of rājaguhya

rājaguhya - royal secret, mystery of kings

Compound type : tatpurusha (rājan+guhya)

• rājan – king, ruler
  noun (masculine)
• guhya – secret, hidden, mysterious
  adjective (neuter)
  Gerundive
  Root: guh (class 1)

अध्यात्मज्ञानम् (adhyātmajñānam) - knowledge of the self (ātman) or spirit, spiritual knowledge

(noun)

Nominative, neuter, singular of adhyātmajñāna

adhyātmajñāna - knowledge of the supreme self, spiritual wisdom

Compound type : tatpurusha (adhyātman+jñāna)

• adhyātman – the supreme spirit, the individual soul, the self
  noun (neuter)
  Prefix: adhi
• jñāna – knowledge, wisdom, understanding
  noun (neuter)
  Root: jñā (class 9)

उत्तमम् (uttamam) - supreme, best, excellent

(adjective)

Nominative, neuter, singular of uttama

uttama - highest, best, excellent, principal

ज्ञात्वा (jñātvā) - having known, having understood

(indeclinable)

Absolutive (gerund)

Root: jñā (class 9)

राघव (rāghava) - O descendant of Raghu, O Rāma

(proper noun)

Vocative, masculine, singular of rāghava

rāghava - descendant of Raghu (a name for Rāma)

patronymic from Raghu

राजानः (rājānaḥ) - kings

(noun)

Nominative, masculine, plural of rājan

rājan - king, ruler

पराम् (parām) - supreme, highest

(adjective)

Accusative, feminine, singular of para

para - supreme, highest, ultimate, distant

निर्दुल्कताम् (nirdulkatām) - freedom from suffering/sorrow, state of being without sorrow

(noun)

Accusative, feminine, singular of nirduḥkhatā

nirduḥkhatā - freedom from pain/suffering, state of no sorrow

derived from nirdulkha (without sorrow) + tā (abstract noun suffix)

Compound type : bahuvrihi (nis+dulka)

• nis – out, forth, without, negation
  prefix
• dulka – pain, suffering, sorrow
  noun (neuter)

गताः (gatāḥ) - attained, gone to, reached

(adjective)

Nominative, masculine, plural of gata

gata - gone, arrived, attained

Past Passive Participle

Root: gam (class 1)