Adjective:

அடுப்படை தீவிர,

epochal's Usage Examples:

The lines of the treaty of Westphalia, six years later, were already laid down by Richelieu; and its epochal importance in European history is a measure of the genius who threw the balance of power from Habsburg to Bourbon.

In political history, the epochal fact which marks the close of ancient times is the decline of the Roman Empire.

Philological rather than theological in character, it marked an epochal change from the old homiletic commentary, and though more recent research, patristic and papyral, has largely changed the method of New Testament exegesis, Alford's work is still a quarry where the student can dig with a good deal of profit.

Synonyms:

epoch-making, significant, important,

Antonyms:

inessential, unimportant, unimportance, insignificant,