essential Synonyms - page 4

inwrought invaluable intrinsical intrinsic internal integral instrumental innermost innate inmost irreducible irremissible material mandatory major mains main life-saving lifeblood leading keystone key inhesion inherited indigenous indefeasibility incumbent inbred inborn inalienable imprescriptible important importance implanted indispensability indivertible inherent inherency inherence ingrained ingenite ingenerate inexistence inevitable inescapable indwelling imperative