One Word Substitution

2501. Medicine that causes vomiting.

Emetic

2502. Spectator’s demand for a song to be repeated.

Encore

2503. A book giving information on all branches of knowledge

Encyclopedia

2504. A poem narrating achievements of a hero.

Epic.

2505. One who is dainty in eating.

Epicure

2506. Government by old people.

Gerontocracy

2506. The rule of saints .

Hagiarchy

2507. Science of health.

hygenics

2508. A word having the same sount but different meaning .

Homonym

2509. Words inscribed on tomb.

Epitaph

2510. The practice of spying .

Espionage