any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt
"The chemistry teacher asked us to test the unknown solution to see if it was an acid based on its ability to turn blue litmus paper red."
street name for lysergic acid diethylamide
"After taking a few hits of that mysterious powder he bought at the underground market, his vision began to blur into swirling colors."
A sour substance.
"The developer spent weeks debugging why their ACID-compliant system failed to maintain data integrity during high-traffic spikes."
Acronym of atomicity, consistency, isolation, and durability., a set of properties that guarantee database transactions are processed reliably
In plain English: An acid is a substance that tastes sour and can burn your skin if you touch it.
"The lemon added a sharp acid flavor to the water."
Usage: When referring to the chemical substance with a sour taste or sharp smell, use acid as a common noun; do not use it for the acronym ACID used in database management systems. Reserve the technical term for contexts involving data integrity and transaction processing.
harsh or corrosive in tone
"an acerbic tone piercing otherwise flowery prose"
"a barrage of acid comments"
"her acrid remarks make her many enemies"
"bitter words"
"blistering criticism"
"caustic jokes about political assassination, talk-show hosts and medical ethics"
"a sulfurous denunciation"
"a vitriolic critique"
Sour, sharp, or biting to the taste; tart; having the taste of vinegar.
"The lemon added a bright, acidic punch to the salad dressing that perfectly balanced the richness of the cheese."
In plain English: Acid describes something that is extremely sour, harsh, or unpleasant to deal with.
"The acid smell of the garbage made me want to leave."
Usage: Use "acid" as an adjective only when describing a literal sour or tart taste, such as in sour milk or unripe fruit. Avoid using it metaphorically for harsh criticism or personality traits, where words like "sharp," "caustic," or "cynical" are more appropriate.
The word comes from the Latin acidus, meaning "sour," which was borrowed into English via French. It originally described a sour taste before being applied to chemical substances with similar properties.