“Clandestine” means kept or done in secret, often to conceal an illicit or improper purpose.
“Arcane” also refers to something hidden that the information is restricted to an inner circle, often making it esoteric or even magical to outsiders.

Similar Words: Arcane, Covert, Hidden, Stealthy, Underground, Surreptitious, Concealed, Secret.

“Cardinal” means of prime importance or fundamental significance; something essential or basic.
“Archetypal” also relating to, or being an original model or a perfect example of a type.
Similar Words: Essential, Principal, Vital, Primary, Crucial, Key, Fundamental.

“Chagrin” means a feeling of distress, humiliation, or embarrassment caused by failure or disappointment.
“Annoyance” also refers to a state of emotion of being slightly angry, irritated, or impatient. It is a mild, unpleasant mental state often caused by a repetitive or minor issue.

Similar Words: Mortification, Discomfiture, Humiliation, Annoyance, Vexation, Shame, Embarrassment.

“Bolster” means to support, strengthen, or reinforce something—often ideas, confidence, or morale.
“Reinforce” also means to strengthen or increase something by adding more support, material, or evidence.
Similar Words: Strengthen, Reinforce, Sustain, Buttress, Corroborate, Substantiate, Fortify.

“Bewilder” means to cause someone to become completely puzzled or confused.
“Bemuse” also means to be confused or puzzled, often combined with a feeling of wry, detached, or tolerant amusement.
Similar Words: Perplex, Baffle, Befuddle, Confound, Mystify, Fluster, Nonplus, Bemuse.

“Blithe” means showing a cheerful and carefree attitude, often in a lighthearted or unconcerned way.
“Jovial” means describing a person, mood, or atmosphere that is very happy, cheerful, and full of good humor.
Similar Words: Cheerful, Joyous, Merry, Lighthearted, Happy, Carefree, Buoyant, Jovial.

“Avid” means having an intense enthusiasm or keen interest in something.
“Rapacious” also means excessively and aggressively wanting to obtain money, material possessions, or other things.
Similar Words: Keen, Enthusiastic, Ardent, Passionate, Zealous, Fervent, Eager, Rapacious.

“Aplomb” means self-confidence or assurance, especially in a demanding or difficult situation.
“Poise” also means graceful and confident composure. Both words convey calmness, self-assurance, and steadiness under pressure.
Similar Words: Confidence, Composure, Self-assurance, Equanimity, Coolness, Poise, Self-possession.

“Berate” means to scold or criticize someone angrily or harshly.

“Reprimand” is a formal or official criticism, often involving authority, which also means to rebuke someone for their behavior. Both words involve the act of criticizing or chastising someone for wrongdoing.

Similar Words: Rebuke, Chide, Castigate, Chastise, Admonish, Reprimand, Reproach.

“Pillage” refers to the act of robbing or looting, especially during times of war or chaos.

“Plunder” is a synonym, meaning to steal goods, especially using force or violence. Both terms describe the act of taking property by force, often with destructive consequences.

Similar Words: Ravage, Plunder, Loot, Robbery.