महाभारतः mahābhārataḥ - book-12, chapter-224, verse-20

इतरेषु ससंध्येषु ससंध्यांशेषु च त्रिषु ।
एकापायेन संयान्ति सहस्राणि शतानि च ॥२०॥

20. itareṣu sasaṁdhyeṣu sasaṁdhyāṁśeṣu ca triṣu ,
ekāpāyena saṁyānti sahasrāṇi śatāni ca.

20. itareṣu sasandhyeṣu sasandhyāṃśeṣu ca triṣu
ekāpāyena saṃyānti sahasrāṇi śatāni ca

20. itareṣu triṣu sasandhyeṣu ca sasandhyāṃśeṣu
sahasrāṇi ca śatāni ekāpāyena saṃyānti

20. In the other three yugas, along with their dawns (saṃdhyā) and twilight portions (saṃdhyāṃśa), the thousands and hundreds (of years) decrease by one unit each.

Words meanings summery:

• इतरेषु (itareṣu) - In the other three yugas (Tretā, Dvāpara, Kali), apart from Kṛta. (in the others)

• ससन्ध्येषु (sasandhyeṣu) - Refers to the yugas including their respective preceding transition periods. (with their dawns (saṃdhyā), along with their transition periods)

• ससन्ध्यांशेषु (sasandhyāṁśeṣu) - Refers to the yugas including their respective succeeding transition periods. (and with their twilight portions (saṃdhyāṃśa))

• च (ca) - and

• त्रिषु (triṣu) - In the three yugas (Tretā, Dvāpara, Kali). (in the three)

• एकापायेन (ekāpāyena) - By the subtraction of one 'thousand' from the main yuga duration and one 'hundred' from the saṃdhyā/saṃdhyāṃśa duration for each subsequent yuga. (by a decrease of one, by the subtraction of one)

• संयान्ति (saṁyānti) - The thousands and hundreds of years diminish progressively in the subsequent yugas. (they go, they proceed, they diminish)

• सहस्राणि (sahasrāṇi) - thousands

• शतानि (śatāni) - The hundreds of years that make up the saṃdhyā and saṃdhyāṃśa. (hundreds)

• च (ca) - and

Words meanings and morphology

इतरेषु (itareṣu) - In the other three yugas (Tretā, Dvāpara, Kali), apart from Kṛta. (in the others)

(pronoun)

Locative, masculine, plural of itara

itara - other, another

Note: Refers to the yugas.

ससन्ध्येषु (sasandhyeṣu) - Refers to the yugas including their respective preceding transition periods. (with their dawns (saṃdhyā), along with their transition periods)

(adjective)

Locative, masculine, plural of sasandhya

sasandhya - accompanied by a saṃdhyā

compound with 'sa' (with) and 'sandhyā'

Compound type : bahuvrīhi (sa+saṃdhyā)

• sa – with, accompanied by
  indeclinable
• saṃdhyā – junction, twilight, dawn, transition period
  noun (feminine)
  Prefix: sam
  Root: dhā (class 3)

Note: Qualifies itareṣu triṣu (yugas).

ससन्ध्यांशेषु (sasandhyāṁśeṣu) - Refers to the yugas including their respective succeeding transition periods. (and with their twilight portions (saṃdhyāṃśa))

(adjective)

Locative, masculine, plural of sasandhyāṃśa

sasandhyāṁśa - accompanied by a saṃdhyāṃśa

compound with 'sa' (with) and 'sandhyāṃśa'

Compound type : bahuvrīhi (sa+saṃdhyāṃśa)

• sa – with, accompanied by
  indeclinable
• saṃdhyāṃśa – twilight portion, part of the transition
  noun (masculine)
  Prefix: sam
  Root: dhā (class 3)

Note: Qualifies itareṣu triṣu (yugas).

च (ca) - and

(indeclinable)

Note: Functions as a conjunction.

त्रिषु (triṣu) - In the three yugas (Tretā, Dvāpara, Kali). (in the three)

(numeral)

Note: Qualifies implicit yugeṣu.

एकापायेन (ekāpāyena) - By the subtraction of one 'thousand' from the main yuga duration and one 'hundred' from the saṃdhyā/saṃdhyāṃśa duration for each subsequent yuga. (by a decrease of one, by the subtraction of one)

(noun)

Instrumental, masculine, singular of ekāpāya

ekāpāya - decrease of one, subtraction of one

Compound type : tatpuruṣa (eka+apāya)

• eka – one
  numeral (masculine/feminine/neuter)
• apāya – decrease, loss, subtraction
  noun (masculine)
  Prefix: apa
  Root: i (class 2)

Note: Specifies the manner of decrease.

संयान्ति (saṁyānti) - The thousands and hundreds of years diminish progressively in the subsequent yugas. (they go, they proceed, they diminish)

(verb)

3rd person , plural, active, present (laṭ) of yā

present active

present stem yā- + 3rd person plural ending

Prefix: sam

Root: yā (class 2)

Note: The subjects are sahasrāṇi and śatāni.

सहस्राणि (sahasrāṇi) - thousands

(noun)

Nominative, neuter, plural of sahasra

sahasra - thousand

Note: Subject of saṃyānti.

शतानि (śatāni) - The hundreds of years that make up the saṃdhyā and saṃdhyāṃśa. (hundreds)

(noun)

Nominative, neuter, plural of śata

śata - hundred

Note: Subject of saṃyānti.

च (ca) - and

(indeclinable)

Note: Functions as a conjunction.