The principal use of ‘definition’ is to eliminate

The correct answer is D) Ambiguity. This is a question on logic and the function of definition. A definition fixes the precise sense in which a term is used, so that a word with several possible meanings is pinned down to one. Its principal job is to remove that uncertainty.

• A) Logical forms: Definitions do not eliminate logical forms. Forms such as syllogisms are studied and validated separately. A definition only tells you what a term stands for.
• B) Rules of grammar: Grammar governs how words are arranged in sentences. Definitions work at the level of meaning, not syntax.
• C) Meaning: This is the trap. A definition gives or states meaning; it does not eliminate it. What it eliminates is the vagueness or double sense that surrounds a term.

The core concept is the function of definition in reasoning: it is a tool for precision. This links directly to Mains, where legal and constitutional drafting depends on definition clauses (for example, the definitions in Article 366) to prevent disputes over interpretation.

Trap: Aspirants pick 'Meaning' because definitions are obviously about meaning. Read the question as asking what is removed, not what is provided.