A Glossary of Common Carseat Terms


How many times have you been looking at carseats and come across a word that you didn’t understand? In this specialized field, we have lots of terms that are important to you as a consumer and parent. Hopefully this list will make reading labels and manuals a bit easier! These terms apply to TYPICAL situations and are terms you’ll see mentioned often here on the blog; however, child passenger safety is a field of exceptions. Read your owners’ manuals for further clarification on your setup.

anti-rebound bar: This is a bar or foot on a rear-facing carseat that sits against the vehicle seatback and prevents or reduces the CR’s ability to rebound during a frontal crash. Some infant seats have an anti-rebound position for their handles when placed in the vehicle.

Australian tethering: A method of tethering a rear-facing carseat to the vehicle seating position’s tether anchor. Britax is the only manufacturer (outside of Australia) that allows this type of tethering for its rear-facing convertibles. Most people choose to use Swedish tethering.

belt path: The portion of the carseat where the seatbelt (or LATCH belt) runs through. Convertible seats have two separate belt paths. For rear-facingconvertibles, it’s typically under the child’s thighs whereas on most forward-facing seats, it’s behind the child’s back.


belt-positioning booster (BPB): This is a carseat for an older and larger child and uses the seatbelt as the only form of restraint. The job of a booster is to simply boost a child up so that the lap belt fits low over the hips/thighs and the shoulder belt fits across the shoulder and not over the throat. While some boosters can be attached to the vehicle using LATCH or a tether, most sit loosely on the vehicle seat.

bight: That crack in the backseat where the upper cushion meets the lower cushion; lower LATCH anchors are typically found here if you have a vehicle equipped with them. To remember the proper spelling, think of this little rhyme: You know you are right when you spell it “bight.”

Britax: Pronounced br∙eye∙tax

buckle: The female portion of the seatbelt that has the release button. This is often on a short webbing belt (called the buckle stalk) that can be twisted up to 3 full twists to maneuver the latchplate out of the carseat belt path, if necessary. A carseat also has a buckle for the harness. The carseat buckle cannot be twisted.

chest clip: AKA a “harness retainer clip,” the chest clip typically consists of 2 plastic pieces that clip together at the child’s armpit level. Its purpose is to keep the harness positioned correctly over the child’s shoulders.

Chicco: Pronounced key∙ko

cocooning: See rebound.

Combi: Pronounced com∙bee

combination carseat: This is a forward-facing only carseat that uses a harness to a specified weight limit, then converts to a belt-positioning booster. Some newer combination seats are referred to as 3-in-1 carseats because they harness, can convert to a highback booster, then can convert to a backless booster.

convertible carseat: This is a carseat that can be used rear-facing to a specified weight limit, then turned forward-facing. Some models also convert to belt-positioning boosters and are typically called 3-in-1 or all-in-one seats.

Diono: Pronounced dee∙oh∙no. Short for Sunshine Kids.

Evenflo: Pronounced eeven∙flow, but there’s no “w” at the end when spelling it properly

Graco: Pronounced gray∙co

harness: The webbing that secures your child to her carseat. It should be snug as a hug!

harness adjuster: The mechanism that adjusts the tightness of a harness. Some have metal levers you push/pull on to loosen the harness, others have a plastic button that presses the metal lever for you. On some infant seats and older combination seats, the harness adjusters are located on the back of the carseat. Try to find a seat that has a front harness adjuster instead for ease-of-use. Some combination carseats have the adjusters on the harness itself at chest-level.

harness slots: These are the slots in the carseat where the harness passes through to the rear of the carseat. Use the harness slots at or below the child’s shoulders on a rear-facing carseat or at or above on a forward-facing seat.

head excursion (HE): The movement of a child’s head forward and out of the carseat. HE can be greatly reduced by using the tether on a forward-facing carseat. See our blog on tethering: https://carseatblog.com/9226/what-is-a-tether.

infant carseat: These “bucket” carseats are rear-facing ONLY carseats for infants and young toddlers. They most often have a base that installs in the vehicle so you can remove the infant seat portion for portability. Most infant seats can now be installed without the base for use in other vehicles or while on vacation.

LATCH: Stands for Lower Anchors and Tethers for CHildren. We often only refer to the lower anchors when talking about LATCH (e.g., Did you use LATCH to install the carseat?). This is a system used for installing your carseat. It is only considered safer than using the seatbelt when the installation is better using LATCH. When installing a carseat with LATCH, do not use the seatbelt at the same time. Using both at the same time places different stresses on the carseat’s belt path and may affect its performance in a crash. Always always always use the tether on a forward-facing carseat (if one is available), even if you install it using the seatbelt.

latchplate: The metal male portion of the seatbelt that gets clipped into the buckle. The latchplate may be locking or free sliding. If the seatbelt has a retractor, the latchplate is typically free sliding. If the latchplate of a lap/shoulder belt is sewn to the seatbelt, the seatbelt has 2 retractors. How fun!

locking clip (lc): The silver metal H-shaped piece that comes with most carseats (except boosters). It locks the lap portion of the seatbelt to the shoulder portion so that the seatbelt remains tight during daily use. Another common use of the locking clip is to take the sideways tip out of rear-facing carseats. See also www.CarSeatSite.com/lockingclips.htm.

lock-off: A device on some carseats that holds the belt tight in lieu of a locking clip. Lock-offs can be pieces that snap together (á la a barrette) or slides where you slide the shoulder belt into place. It’s important to read your carseat manual to determine if you should use one or both lock-offs.

Peg Perego: Pronounced peg pear-uh-go

rebound: The action of a rear-facing carseat when the top portion of it moves toward the back seat upon pushing or collision. It’s sometimes called “cocooning.”

 retractor: The mechanism that provides tension on a lap/shoulder belt and some lap-only belts. It allows the seat belt to retract and pull out and is often hidden inside the panels on the walls of the vehicle or in the vehicle seatback.

Types of retractors:

ELR (Emergency Locking Retractor): locks only on sudden stop or collision
ALR (Automatic Locking Retractor): is always locked when pulled out; once it’s buckled, it gets tighter and tighter, like an Anaconda snake
switchable: locks on sudden stop or collision, or when pulled out all the way; Chrysler/Dodge/Jeep vehicle owner manuals refer to this retractor mode as “ALR”–because you must change the vehicle belt into locked mode, it is a switchable retractor

Seat Belt Syndrome: A group of injuries to the abdomen that occur when the lap portion of the seatbelt is positioned over the soft abdomen instead of the hard hip bones. Internal organs, such as the bladder, intestine, stomach, liver, and pancreas can be perforated. If severe enough, the vertebrae and spinal cord may be damaged. A belt-positioning booster can prevent such injuries.

shoulder belt guide: The piece on a booster seat that positions the shoulder belt for the child.

splitter plate: The metal piece on the back of the carseat that attaches the ends of the harness to the harness adjuster strap.

submarining: When a child’s hips slide down toward the crotch strap in a carseat or under the lap portion of a seatbelt when using a belt-positioning booster or just the seatbelt alone. Injuries from submarining include Seat Belt Syndrome.

Swedish tethering: A method of tethering a rear-facing carseat toward the front of the vehicle using a front seat leg or front seatbelt anchor. Britax and Sunshine Kids (Diono) convertibles, and the Combi Cocorro can be tethered rear-facing using this method. A short strap, called the tether connector strap (AKA D-ring), is usually needed to wrap around the seat leg.


tether anchor: The metal piece behind a seating position to which the carseat’s tether strap is attached. May also be a loop of webbing in pick-up trucks.

tether strap: A long webbing belt located at the top back of a carseat with a hook on the end. See also https://carseatblog.com/9226/what-is-a-tether.


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