A number of idiomatic expressions refer (often hyperbolically, or with lighthearted exaggeration) to units of English measure to describe something figuratively or make an observation. This post lists and explains many such phrases.
To be “every inch a (something)” or “every inch the (something)” is to so closely match a stereotypical look or embody a trait that the comparison holds thoroughly, figuratively, from beginning to end. “Within an inch of (one’s) life” means “to an extreme degree”; to beat someone to within an inch of that person’s life is to physically attack that person so severely that he or she is very close to (figuratively, an inch away from) death.
To move by inches, or inch by inch, or to inch along (or inch one’s way along) is to progress very slowly, in very short increments, whether literally or figuratively. (Other prepositions may, depending on the context, replace along.) “Come within an inch of” refers figuratively to very nearly accomplishing a goal or experiencing something. The phrase “every inch” (sometimes “every square inch”) hyperbolically refers to complete coverage, as in “Every inch of the room was strewn with toys.”
To say “Give (someone) an inch and (that person) will take a mile” is to express that someone given a modest concession will take advantage to extract more from the giver. “Give an inch,” on its own (or “Budge an inch” or “Move an inch”), is usually part of a statement alluding to someone’s unwillingness to compromise, as in “You never give an inch.” To say that someone does not trust someone else an inch is to express an utter lack of faith in that person.
Something that is inch-perfect is extremely accurate or well judged.
Idioms that include the word foot almost invariably pertain to the anatomic feature rather than the unit of measurement, but to say that one would not touch a person or a thing with a ten-foot pole suggests in no uncertain terms that one does not want to be associated with that person or thing. The phrase “all wool and a yard wide” alludes to the high quality of a person or an object, while to say that someone goes or went “the whole nine yards” expresses that the person is or was very thorough in accomplishing something.
A country mile is a longer-than-expected distance, perhaps from the notion that traveling a mile in a rural area seems longer than passing over that distance in a more congested area. The expression “A journey of a thousand miles begins with a single step” expresses that a formidable task is easily begun by focusing on a small initial effort.
“A mile a minute” suggests doing something, such as talking, at extreme speed in a state of excitement. To say that someone can detect or observe something from a mile away hyperbolically suggests that the thing is easily noticed; however, to say that someone is miles away (or a million miles away) is to note that the person is preococcupied and not attending to a nearby activity, while to be miles from anywhere or nowhere is to literally be physically isolated. Saying that someone is a mile off or missed by a mile means that the person is mistaken or wrong to a great degree; the latter can also literally refer to someone missing a target by far or being very inaccurate in aim.
“A miss is as good as a mile” means that a small failure is as just as significant as a large one. To be miles apart from agreement suggests that the parties are very much opposed. The phrase “by a mile” refers hyperbolically to accomplishing or failing to accomplish something by a significant amount. “For miles” (and “for miles and miles”), however, neutrally refers to at least several miles in such statements as “The property extends for miles in each direction.”
To go the extra mile is to make greater effort than is required, while something that stands out or sticks out a mile is extremely obvious.
“More bounce for the ounce” is slang referring to getting more value for one’s money with one product or investment than another. “An ounce of prevention is worth a pound of cure” means that a minimal amount of forethought has the same value as a significant expenditure of effort to resolve an issue that developed because of lack of foresight. Other comparisons are made between “commonsense and theory” and between “discretion and wit” (in the latter case, encouraging people to withhold clever comments that may embarrass another person).
To pack or pile on the pounds is to quickly gain weight. The phrase “pound for pound” means “considering the weight involved.” (In combat sports such as boxing, participants who compete in different weight classes are sometimes ranked in skills according to various criteria; this type of ranking is called “pound for pound.”)
“Pound of flesh,” from Shakespeare’s play The Merchant of Venice, alludes to an unreasonable debt, based on the character Shylock’s insistence on receiving a pound of flesh that a borrower agreed, with overconfidence, to surrender as collateral.
The phrase “800-pound gorilla” refers metaphorically to an entity so powerful that it can ignore limitations others are bound to. (It alludes to the riddle “Where does an 800-pound gorilla sit?” the answer to which is “Wherever it wants.)
The phrase “come down on (one) like a ton of bricks” figuratively expresses that punishment will be or has been dealt out severely, as if the person being punished was or will be buried beneath a crushing weight. When someone refers to “tons of” something, he or she is hyperbolically expressing abundance. To say that something “weighs a ton” is to exaggerate the weight of an object that must be carried or lifted that is unexpectedly or excessively heavy.