Ant. Activity, energy.

Indomitable. Unyielding, unconquerable, invincible; untamable, irrepressible, indefatigable.

Ant. Effortless, feeble, languid.

Indorse. Superscribe; sanction, approve, vouch for, confirm, ratify; accept.

Ant. Protest, repudiate, renounce, abjure, cancel.

Induce. Influence, impel, move, prompt, instigate, persuade, actuate, urge, incite, spur, prevail upon; cause, produce, effect, bring on.

Ant. Prevent, disincline, dissuade, deter, hinder, restrain.

Induction. Introduction, installation, inauguration, institution; conclusion, inference, generalization, inductive method; collection, collation, application.

Ant. Statement, hypothesis; deduction; subtraction; principle, class, law, proposition, argumentation, discourse.

Indulge. Gratify, yield, satisfy; humor, pamper, favor; allow, permit, suffer, cherish, foster, harbor; spoil, revel, grovel.