One Word Substitution

Anarchy literally means 'absence of government' or 'without rulers' (from Greek 'an' = without, 'arkhos' = ruler). Monopoly is exclusive control of a commodity, Aristocracy is rule by the elite, and Amnesty is a pardon - none of these mean absence of government.

Aquatic means 'living in water' (from Latin 'aqua' = water). Terrestrial means land-dwelling, Tropical refers to climate zones, and Celestial means heavenly/sky-related - none describe water-dwelling animals.

Amphibious means 'capable of living both on land and in water' (from Greek 'amphi' = both, 'bios' = life). Frogs are classic examples. Aquatic means only water, Terrestrial means only land, and Avaricious means greedy.

Atheist means 'one who does not believe in the existence of God' (from Greek 'a-' = without, 'theos' = god). Pantheist believes God is everything, Theist believes in God, and Fanatic shows excessive zeal.

Cannibal means 'man or animal that feeds on its own species'. The term comes from the Carib people. Carnivorous eats meat generally, Herbivorous eats plants, and Avaricious means greedy - neither specifies eating one's own kind.

Autocracy means 'absolute government by one person' (from Greek 'auto' = self, 'kratos' = power). Aristocracy is rule by the elite, Democracy is rule by the people, and Monopoly is economic control.

Effeminate means 'having characteristics more like a woman than a man' - typically describing manner or behavior. Masculine means manly, Robust means strong/healthy, and Feminine means womanly - only Effeminate captures the idea of a man with womanly characteristics.

Ambidextrous means 'able to use both hands equally well' (from Latin 'amb-' = both, 'dexter' = right/handed). Atheist relates to belief in God, Equestrian relates to horse-riding, and Pedestrian means walking.

Equestrian means 'one who rides on horseback' (from Latin 'equus' = horse). Pedestrian walks, Cosmopolite is worldly, and Spectator watches - none relate specifically to horse riding.

Garrison means 'soldiers in a fortress' stationed for defense. Rabble is a disorderly crowd, Force is general military power, and Swordsman is one skilled with swords - none specifically mean soldiers stationed in a fortress.

Regicide means 'the murder of a king' (from Latin 'rex' = king, 'cidium' = killing). Parricide is killing a parent, Matricide is killing a mother, and Fratricide is killing a brother - the suffix '-cide' means killing, but the prefix must specify the victim.

Brittle correctly describes something that is hard but breaks easily. Crisp means fresh/firm, fragile means easily broken (without the hard aspect), and vulnerable means exposed to harm.

Gregarious correctly describes animals that live in groups/flocks. Nomadic means wandering, pastoral relates to shepherding, and barbarous means uncivilized.

Honorary correctly describes a position held without salary. Gratis means free (but can apply to things), ad hoc means for a specific purpose.

Indispensable correctly means something that cannot be done without. Inaccessible means unreachable, indelible means cannot be erased, and incorrigible means cannot be corrected.

Mercenary correctly describes someone motivated primarily by money. Loquacious means talkative, honorary means unpaid, and equestrian relates to horse riding.

Oligarchy correctly means government by a few powerful people. Anarchy is absence of government, aristocracy is government by the elite, and monopoly is market control by one entity.

Omnipresent correctly means present everywhere simultaneously. Omniscient means all-knowing, omnipotent means all-powerful, and omnivorous means eating all food types.

Fratricide correctly means killing one's brother. Regicide is killing a king, matricide is killing one's mother, and parricide is killing a parent or close relative.

Panacea correctly means a remedy for all diseases or problems. Penchant means a strong liking, and cure is too general.

Omnivorous correctly describes an organism that eats both plants and animals - anything and everything. Herbivorous eats only plants, carnivorous only meat, and cannibalistic eats one's own species.

Irrevocable correctly means something that cannot be changed or recalled once done. Irreparable means cannot be fixed, irritable means easily annoyed, and insatiable means cannot be satisfied.

Verbatim correctly means word-for-word, using exact words. Verbose means using too many words, linguist is a language expert, and plagiarism is stealing someone's work.

Inflammable means capable of being easily set on fire. Don't confuse it with infallible (incapable of being wrong), inimitable (too unique to copy), or insoluble (cannot be dissolved).

Congregation specifically means a group of people assembled for religious worship. Assembly is any gathering, audience are spectators or listeners, and crowd is a large group without specific purpose.