Can You Give Some Words That Happen To Be Their Own Antonyms In Usage ?

A word with two meanings is called a heteronym.

Your type of heteronym is an auto-antonym or contranym.

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Cleave apart and Cleave together.

anabasis – military advance, military retreat

aught – anything, nothing

bolt – secure, run away

buckle – fasten, fall apart

consult – ask for advice, give advice

copemate – partner, antagonist

custom – usual, special

dust – add fine particles, remove fine particles

enjoin – prescribe, prohibit

fast – quick, unmoving

garnish – enhance (e.g., food), curtail (e.g., wages)

handicap – advantage, disadvantage

left – remaining, departed from

mean – average, excellent (e.g., “plays a mean game”)

out – visible (e.g., stars), invisible (e.g., lights)

put out – extinguish, generate (e.g., something putting out light)

quiddity – essence, trifling point

screen – show, hide

transparent – invisible, obvious

weather – withstand, wear away

The only real example I can think of is “bad.” The literal meaning of “bad” is generally something of poor or inferior quality. But, often the word “bad” is used in popular slang to refer to something that is especially good and of high quality.

A few other ideas come to mind, but the particular word is not really it’s own antonym. But, in the context it is used it has the opposite meaning. This will be the case with many words that are used sarcastically such as when someone rolls their eyes and says, “Oh, yeah, that’s cool.” when the tone of their voice and other mannerisms clearly indicates they don’t believe what they just said and what they really meant was, “That’s really nerdy.”

Well… stop isn’t really the opposite of help. Help simply has several meanings depending on context.