The Christmas Light Glossary

Jump to a letter, or scroll through. Where a term has products to match, we have linked straight to them.

#

5mm wide-angle The LED shape used in commercial mini lights. The wide-angle lens throws light out to the sides for a full, even look when you wrap trees and greenery. Shop mini lights

A

All-in-one clip A clip that holds lights on both the shingle and the gutter, so you carry one clip up the ladder instead of two. Shop clips

Amperage (amps) The electrical load a run of lights draws. It decides how many bulbs or strands you can connect end to end before you trip a breaker. Because LED lights draw far less than incandescent, you can run much longer lines on one circuit.

B

Blank wire Zip cord with no sockets, used to carry power across a gap between two lit sections without adding bulbs. Shop socket wire & plugs

Bulb base The screw end of a bulb that threads into the socket. C7 uses the smaller E12 candelabra base, and C9 uses the larger E17 intermediate base.

C

C7 A retrofit bulb about three-quarters of an inch wide on an E12 base, used on windows, walkways, railings and smaller homes. Shop C7 bulbs

C9 The larger retrofit bulb, about one and a quarter inches wide on an E17 base, and the standard for rooflines and ridgelines. Shop C9 bulbs

Candelabra base (E12) The smaller screw base used by C7 bulbs.

Clip The fastener that holds a bulb or wire to a surface. The right one depends on the surface: a shingle tab for roofs, a gutter clip for gutters, or an all-in-one for both. Shop clips

Cool white A crisp, slightly blue-white LED color, popular for a clean, modern look.

E

E12 and E17 Bulb base sizes. E12, the candelabra base, fits C7 bulbs. E17, the intermediate base, fits C9 bulbs. Match the bulb base to your socket wire.

F

Faceted bulb A bulb with cut, diamond-like sides that sparkle and scatter light. The opposite is a smooth bulb.

G

G40 A round globe bulb about an inch and a half across, used for patios, trees and cafe-style runs. Shop C7 & G40 bulbs

Gutter clip A clip that grips the lip of a gutter, for running lights along the gutter line. Shop clips

I

Intermediate base (E17) The larger screw base used by C9 bulbs.

L

LED retrofit bulb An LED bulb that twists into an existing socket and can be replaced one at a time, so a single failure never takes out the whole run. Shop bulbs

M

Male and female plugs The two ends that connect a run to power. The male plug has the prongs, and the female end receives them or plugs into an outlet.

Mini light A small 5mm wide-angle LED on a strand, used for wrapping trees, bushes and greenery. Shop mini lights

N

Net light A pre-spaced grid of mini lights that drapes over a bush or hedge for an even look in minutes. Shop net lights

P

Permanent lighting (permanent track) Low-profile LED fixtures mounted in a track under the roofline. They stay up all year and change colors from a phone app. See permanent lighting

Photocell A small light sensor that turns the lights on at dusk and off at dawn on its own. Shop timers & accessories

Pitch Hopper A roof ladder stabilizer that gives a ladder a stable, more level base on a pitched roof. Shop the Pitch Hopper

R

Retrofit bulb Any bulb made to replace another in an existing socket, like the C7 and C9 LEDs that twist into socket wire.

RGBW A bulb with red, green, blue and white LEDs in one, so it can show full color and a true, clean white. Common in permanent lighting.

Roofline The edge of the roof where C9 bulbs are typically run.

S

Shingle tab A clip that slides under a shingle to hold a bulb upright on the roofline. Shop clips

Smooth bulb A bulb with a smooth, unfaceted surface for a cleaner, steadier glow. The opposite of faceted.

Socket spacing The distance between sockets on socket wire, commonly 12 inches for a full look or 18 inches for a lighter one. Shop socket wire

Socket wire (socket cord) Zip cord with sockets spaced along it, cut to the length of each run so the install looks clean and custom. Shop socket wire & plugs

SPT-1 Socket wire with a thinner insulation jacket, the standard for custom-cut professional runs. Shop SPT-1 socket wire

SPT-2 Socket wire with a thicker jacket for higher-amp loads and very long runs. Most LED installs do not need it.

Steady-lit Mini lights that stay on steadily, as opposed to twinkle. Shop mini lights

Strand (stringer) A length of pre-wired lights, like a set of mini lights.

T

Timer A device that switches the lights on and off on a schedule, either mechanical or triggered by a photocell. Shop timers

Twinkle Mini lights that flicker on and off at random for a bit of movement, the opposite of steady-lit.

V

Vampire plug A plug with internal prongs that pierce the wire's insulation to make a connection, so you do not have to strip the wire. Shop plugs

W

Warm white A soft, yellow-white LED color that reads closest to classic incandescent, and the most popular choice.

Z

Zip cord Two-conductor wire that pulls apart, or zips, so you can attach plugs. Socket wire is a zip cord with sockets added.

Zip plug A plug you attach to the end of socket wire to power the run. Shop plugs