Aside from the way uniformed folks seem to speak in acronyms - "I was on the FOB when the IDF hit, so I radioed the TOC" - there's also a series of commonly used phrases which deserve some attention.
"15 minutes prior to 15 minutes prior"
Military people are taught that they must show up to everything (especially an official formation) at least 15 minutes early.
The 15 minutes to 15 minutes arises as the order filters down through the ranks. The captain wants everyone to meet at 0600, so the master sergeant wants folks to arrive at 0545, and when it finally hits the corporal people are told to show up at midnight.
"A good piece of gear" (in reference to people)
Only in the service is it OK to refer to one of your coworkers or (worse yet and most frequently) a person working for you in a section you manage as "a good piece of gear."
"Back on the block"
Refers to the time before service, when a servicemember was a "nasty" civilian. (Nasty in the military generally means unkempt.)
"Blue falcon"
Phonetic slang for "Buddy F-----."
A Blue Falcon is someone who blatantly throws another Marine/soldier/sailor/airman under the bus.
"Breaking it down Barney-style"
Refers to the kid show "Barney and Friends." When something is broken down "Barney-style," it's being explained as if to a child.
"Days and a wake-up"
A "wake-up" refers to the last day you will be some place (generally while deployed). So, if a servicemember is getting ready for bed on a Sunday, and flying out on a Friday, he'll say "four days and a wake-up."
A "drug deal"
When personnel or materiel are obtained through unofficial channels.
"Embrace the suck"
Military service isn't all fun. In fact, it is mostly suck.
For every five seconds of hanging out of a helicopter, there are countless eternities spent enduring safety briefs and doing mundane tasks (picking up cigarette butts, buffing floors, toilets, etc.). And then there is the unpleasantness of being pinned beneath and unable to escape an ever-present rank structure.
Troops are encouraged to embrace this sad reality.
"Field strip"
Literally refers to taking apart to the extent authorized for routine cleaning, lubrication, and minor repairs.
Field stripping can also be used informally to describe taking apart anything.
If a Humvee becomes stuck or broken outside of base, troops will field strip it of anything classified or of value prior to leaving it behind.
If you park your car in a bad part of town, it may be on cinder blocks by the next morning, completely field stripped.
"Full battle-rattle"
This phrase refers to all the gear servicemen and women are required to carry outside the wire. Generally: flak jacket with protective plates, Kevlar, 180 rounds of ammunition, water, rations, rifle.
It's called "battle rattle" because - unless we're talking about Navy SEALs - walking with all this stuff usually makes noise.
"Gear adrift, is a gift"
Leaving something unattended is your own fault.
Conversely, someone who takes unattended gear has not stolen it, they've "tactically acquired" it. Needless to say, if they get caught, it's still larceny under the Uniform Code of Military Justice. Tactical acquisition is taught in boot camp, where recruits from one platoon will prey on another possibly less-aware platoon in order to get supplies and bragging rights.
"Good initiative, bad judgement"
When a problem needs to be solved but the selected means of solving the problem is itself more problematic.
Generally, it shows "good initiative" because the problem might have been above the pay grade of person trying to solve it.
"Grunt by association"
Said as a compliment: Someone who does not have the official qualification in an infantry field, who has worked on a daily basis with the infantry.
Often said of Artillerymen or drivers, usually folks augmented for periods of time deployed with the infantry.
"High speed, low drag"
Literally a reference to aerodynamics, but often used figuratively to describe pairs of sunglasses, cars, or just about any piece of "gear."
Used most frequently by total tool-bags.
"Lance corporal underground"
Another Corps-specific phrase. Refers to the somewhat ill-informed, ubiquitous network of junior Marines. Word seems to spread around this network like viral content and largely reflects what junior personnel really feel about a subject, course of action, or senior leader.
"Mandatory Fun" or "Mandofun"
Office dinner parties or get togethers that are mandatory. Sometimes these are just understood as mandatory, other times the order is given expressly.
"No impact, no idea"
If a shooter on the range is so far off target that spotters don't see an impact. Used loosely to mean that the speaker doesn't understand an idea, or that someone is totally clueless.
Similar to "high and off to the right," which is the military equivalent of "out of left field" - a personality type gone crazy, or an idea that no one saw coming.
"Nut to Butt"
Very literally, put your nuts on the butt in front of you - said specifically when space is tight or when a situation dictates close proximity of many bodies.
"Police call"
A police call is when an entire unit lines up and walks across a certain area looking for trash.
"Policing," on the other hand, is when a unit internally checks the behavior of its members, or when an individual is ordered to take care of his or her own outward deficiencies (i.e. "Police that mustache!")
"Pop smoke"
Refers directly to when troops use smoke to signal an incoming helicopter.
In vernacular, it means to "leave in a hurry."
"Pucker factor"
Refers to the anus and a frightening situation.
"Rainbow PT gear"
Rainbow means that the unit is wearing whatever sporty gear they want to wear to do "physical training," that the unit will not be in any matching PT uniform.
"Secret squirrel"
Intelligence personnel, secret communications, classified ops, or someone with higher classification
"Semper I, (F--- the other guy)"
Marine Corps-specific terminology. Adapted from the phrase Semper Fidelis, the service's motto, which means Always Faithful.
"Semper I" is generally evoked when a Marine is perceived to have taken a course of action that either directly adversely effects a fellow Marine, or does so by omission, while simultaneously benefiting the original Marine.
"Smoking and joking"
Being unproductive, horsing around, or literally smoking and joking.
"Soup sandwich" or a "S--- sandwich"
A person or situation that is incredibly screwed up. If it's a situation, often "everyone has to take a bite" of said soup sandwich.
"Standby to standby" and "hurry up and wait"
Believe it or not, the military is government, and government isn't always efficient.
"Standby" is what's called a "preparatory command." Usually the order to standby alerts a unit that it will be receiving some kind of marching orders - "standby to launch."
Unofficially, it's used to tell junior members to be ready and wait. Often, troops find themselves waiting for long periods of time due to logistics or command indecisiveness.
Said sarcastically, "standby to standby" means that a unit is waiting in order to wait some more.
"Hurry up and wait," also said sarcastically, pokes fun at the military's propensity to perform tasks quickly, and then sit idly (yet no less ready) to perform another task for long periods of time.
"Squared away" (or "locked on" or "a hard charger")
Squared away in general means that someone is without reproach, but usually when service people say someone is squared away it is a compliment which indicates exemplary, above average service.
On the flip side, when someone is "unsat," they have performed some action or are themselves well below the required standards.
"Voluntarily Told, Voluntold"
There are two different kinds of voluntold:
A. The gunny walks into the office and says, "Man, wouldn't the floor look nice if somebody buffed it?" Which means,"Buff the floor."
B. "I need two volunteers to stand out in front of Best Buy this Saturday collecting Toys for Tots."
" ... "
"Jones, Smith, you're collecting Toys for Tots this weekend."
"Zero Dark Thirty"
Until the movie came around people largely didn't know what this meant. In specific, it refers to the 24-hour time 0030, or 12:30 a.m.
At times it's used loosely to mean "really early."
Also: "Zero Stupid Thirty" to deride formations deemed unnecessarily early.