Incursion. Inroad, raid, invasion, irruption, descent, foray, sally, encroachment.

Ant. Encampment, retreat, abode, settlement.

Indebted. Owing, obliged, beholden, under obligation.

Ant. Disobliged, unbeholden.

Indeed. Truly, really, verily, positively, absolutely, in fact, veritably, certainly, in truth; strictly, in point of fact.

Ant. By no means, not at all.

Indefatigable. Unwearied, untiring, persevering, persistent, assiduous, sedulous, unremitting, never-tiring, unflagging; incessant, indomitable.

Ant. Idle, indifferent, indolent.

Indelible. Ineffaceable, indestructible, ingrained, indefeasible, irreversible, persistent.

Ant. Mutable, evanescent, transient, effaceable.