Correct Terms for Parts of Windows and Doors You Thought You Knew
We Speak Windows and Doors Fluently
At Door Store and Windows, we spend a lot of time talking to customers about how to improve and enhance their homes. And, while we’re proud to be Louisville’s Window and Door Experts, we’ve also accidentally become experts in translating the funny “window and door” terms we hear.
It’s always helpful to know the correct terminology, and our recent blog article talked through the official terms for windows and door parts. But, we’ve heard every “almost right,” “do you actually mean this?” and “let me take a stab at what you’re looking for” term, and we can always figure out what you really need.
In this guide, we’ll walk through terms we hear that are often confused with official parts of windows and doors. If you’re guilty of using one of these incorrect terms, don’t worry, we’re here to talk you through it.
Doors: An “Opening” Act
From grand entryways to backyard patios, doors come in many forms—and with many names. Here’s a breakdown of commonly confused terms and what you should know:
Our customers often start with a simple request, “I’d like a door with window glass in it.” Here is a list of what you may be looking for:
- Entry Doors – Points of access from the exterior to the interior of your home. These could be on the front, back or sides of the house.
- Scenic Doors – Expansive glass units like multi-slide or a bi-fold systems designed to reduce solar heat and maximize natural light.
- Patio Doors – Any door leading to a backyard or deck.
- Storm Doors – A secondary door frame installed outside an entry door that offers protection from the weather.
French Door
A French door is a door with multiple glass panes that run the length of the panel. It is a common misconception that all French doors are double doors. But, French doors can be a single door or double doors. If you’re after that classic, light-filled look, be sure to say French door. (Fake French accent not required, but always appreciated.)
This is an example of a single French door:

Single French Door
Here is what most people imagine when they think of French doors:

Double French Doors
Bi-Fold Door
“Zig-Zag door” is actually a bi-fold door which is made up of two or more hinged door panels that fold against one another when opened. Bi-fold doors are commonly used for patio entrances or between interior and exterior home spaces. Bi-fold doors do resemble zig-zags but that is not an official term.

Bi-fold Door
3-Panel Patio Door
If you are looking for a door with door-sized windows on the sides you are looking for 3-panel patio door which includes three large window glass panels, one or more of which may slide or open on a hinge.
Sliding Door or Gliding Door
A sliding door is the most common term for doors that move horizontally along a track and often provide outstanding views to the outdoors. These doors usually consist of large glass panels and may be part of a larger exterior frame built for energy efficiency. Some people refer to them as, “gliding doors.” The most important thing is your sliding door should glide. If it isn’t gliding, it is time for your sliding door to be replaced.
Sidelights
Sidelights are the “windows next to your doors” so that is usually what we hear. We’ve heard these described in various ways, but sidelights is the official term for the narrow, vertical window units on either side of an entry door.

Sidelight
Skylights
Speaking of sidelights, we have had many people refer to them as “skylights next to the doors.” So, let’s talk about skylights. Skylights are also called roof windows because they are windows installed in your roof or ceiling.
Door Sweep
You might have always thought about it as “that rubber thing under the door,” but it’s actually called a door sweep or a door bottom. It helps block drafts and increase energy efficiency.
Deadbolt Lock
A deadbolt lock is a separate locking mechanism that provides added security, often placed above your standard door handle. You might have called it “the top lock” or “extra lock,” but “deadbolt” is the industry term.
Weather stripping
Weather stripping refers to the process of sealing the gaps around door frames and window openings to prevent air and water from entering or escaping. It utilizes strips of material, often made of rubber, foam, felt, vinyl, or even copper and is essential for energy-efficient homes.
Windows: Let’s “Clear” Things Up
When it comes to using correct window and window frame terms, we’ve seen a lot of glassy stares. But windows come in more varieties and functions than you might realize. Here’s how to talk about them like a pro.
Awning Windows
You might have described them as “lift-up windows,” but knowing the technical name helps ensure you get the right hardware and operation. An awning window is an operable window that is hinged at the top and opens outward from the bottom, often using a crank.

Awning Window
Casement Windows
We’ve probably heard all the slightly incorrect names for a casement window. It swings outward, like a door, and is often opened with a crank or lever mechanism. It’s one of the most energy-efficient types due to its tight seal. We’ve heard them called “swinging windows,” “crank windows,” “push-out windows,” “windows that go out”, “windows that open like a door”…well, you get the idea.

Casement Window
Double-Hung Windows
A double-hung window features two operable window sashes that slide vertically. The upper sash and lower sash can both move, which improves ventilation and ease of cleaning. You might have called these “up-and-down windows” or “push-up windows.” While those names describe the movement, “double-hung” captures the full functionality of being able to open both the top and bottom.

Double Hung Window
Transom Window
Okay, we have to admit — this name is probably tricky to recall. A transom window sits horizontally above a door or larger window and is often fixed, though sometimes operable. But, you could certainly describe them as “windows above the door,” and we promise we’ll know what you’re talking about!

Transom windows above Sliding Doors
Muntin Bars and Grilles
This is one of our favorites because the names are entertaining! “Sticks in My Window,” “Tic-Tac-Toe Board,” or “Squares on My Window” to name a few. They all refer to the strips that separate glass panes within a window frame. These features create simulated divided lite designs for decorative elements and are often made of decorative wood or composite material.
Seal Failure
We hear this many times, “I can’t get my windows clean!” If you see condensation or fog between multiple panes of insulating glass units, it’s likely due to seal failure. Yes, you can describe this as “foggy windows,” but saying “seal failure” really gets to the root of the problem, and this problem reduces both clarity and energy efficiency.
Remember, Your Home Has a Language All Its Own
Staying informed on all the correct terminology is really our job, not yours, and we’re always ready to talk through your home improvement needs, no matter what words you use. Whether you’re ordering replacement windows or upgrading your entryways we’re ready to clear up any confusion you might have.
Any time you need help identifying what you’re looking for, we’re always happy to walk you through it at Door Store and Windows. Contact us or stop by—like we said, we speak window and door fluently!