Less has 11 different meanings across 5 categories:
A smaller amount or quantity.
"She used less sugar in her coffee today because she was trying to cut down on calories."
"The less is that I don't have enough money to buy this car."
Usage: In standard English, do not use "less" as a standalone noun to mean a small amount; instead, describe the quantity directly using words like "a smaller amount." The word "less" functions only as an adjective or adverb and should be paired with a noun, such as in "less money," rather than standing alone.
To make less; to lessen.
"The new tax policy aims to reduce inflation by making prices less volatile over time."
In plain English: To make something smaller by taking away part of it.
"The committee decided to less the number of members by removing two people."
Usage: The word "less" functions only as an adjective or adverb and has no standard usage as a verb in modern English. Instead of saying "to less," you should use the verbs "reduce," "decrease," or "diminish."
(comparative of `little' usually used with mass nouns) a quantifier meaning not as great in amount or degree
"of less importance"
"less time to spend with the family"
"a shower uses less water"
"less than three years old"
(nonstandard in some uses but often idiomatic with measure phrases) fewer
"less than three weeks"
"no less than 50 people attended"
"in 25 words or less"
used to form the comparative of some adjectives and adverbs
"less interesting"
"less expensive"
"less quickly"
comparative degree of little
"The new recipe uses less sugar than the original version, making it slightly healthier without sacrificing sweetness."
In plain English: Less means to have, do, or be smaller in amount than before.
"It is less cold today than it was yesterday."
Usage: Use "less" only when modifying uncountable nouns or abstract concepts to indicate a smaller amount, such as in "less water." Avoid using it with plural countable items; instead, use "fewer" for those cases.
comparative form of little: more little; of inferior size, degree or extent; smaller, lesser.
"The new phone has less storage than the previous model."
Minus; not including
"The final price was less shipping and taxes."
unless
"You can't borrow my car less you bring me a ride back home."
The word "less" comes from Old English, where it originally meant smaller. It traveled into modern usage as the comparative form of "little," reflecting its ancient root meaning to shrink or grow thin.