Independent buying guides for 3D printing

3D Printing Glossary: 22 Terms Explained

The words that show up in 3D printing specs, reviews and how-to guides, explained without jargon. Open any term for the full explanation and what to look for when buying.

Build volume
Build volume is the maximum width, depth and height a printer can produce in a single print job.
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Direct drive extruder
A direct drive extruder mounts the motor right above the hotend, giving better control over flexible filaments than a bowden setup.
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Elephant's foot
Elephant's foot is a bulge at the base of a print caused by the bottom layers being squished slightly wider than the rest.
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FDM
FDM is the most common home 3D printing process, building parts by melting plastic filament and depositing it layer by layer.
Read more about fdmRelated: Best FDM 3D Printers for Reliable Everyday Prints (2026)
First layer
The first layer is the foundation of every print, and level bed plus correct nozzle distance fix most adhesion failures.
Read more about first layerRelated: Best Bed Leveling Sensors for Perfect First Layers (2026)
Hardened steel nozzle
A hardened steel nozzle resists wear from abrasive filaments like carbon fiber or glow-in-the-dark blends that erode brass quickly.
Read more about hardened steel nozzleRelated: Best Hardened Steel Nozzles for Abrasive Filaments (2026)
Infill
Infill is the internal support structure inside a print, controlling strength, weight and material use through density and pattern.
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Layer height
Layer height is the thickness of each printed layer, controlling the tradeoff between print speed and surface smoothness.
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Nozzle diameter
Nozzle diameter is the width of the hole plastic extrudes through, affecting print speed, detail and minimum wall thickness.
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PEI sheet
A PEI sheet is a build surface that grips a hot print firmly and releases it easily once it cools back down.
Read more about pei sheetRelated: Best PEI Build Plates for Strong First Layers (2026)
PETG
PETG is a tougher, more heat-resistant filament than PLA that strings more easily and needs higher print temperatures.
Read more about petgRelated: Best PETG Filament for Strong, Durable Prints (2026)
PLA
PLA is the easiest common 3D printing filament, printing around 190 to 220C with minimal warping and no enclosure needed.
Read more about plaRelated: Best PLA Filament for Clean, Easy 3D Prints (2026)
Resin (SLA/MSLA)
Resin printing cures liquid photopolymer with light instead of melting filament, giving very fine detail at the cost of mess and fumes.
Read more about resin (sla/msla)Related: Best Resin 3D Printers for Sharp, Detailed Models (2026)
Retraction
Retraction pulls filament backward slightly during travel moves to stop the nozzle from oozing plastic where it should not.
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Slicer
A slicer is software that converts a 3D model into printer instructions, setting layer height, infill, supports and temperatures.
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Stringing
Stringing is thin hairs of plastic left between parts of a print, usually caused by oozing during travel moves.
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Support structures
Support structures are temporary printed scaffolding that hold up overhangs and bridges until the model can stand on its own.
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Temperature tower
A temperature tower is a test print that steps nozzle temperature down every few layers to find the best setting for a spool.
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TPU
TPU is a flexible, rubber-like filament used for phone cases, gaskets and grips, printed slowly and best on a direct drive extruder.
Read more about tpuRelated: Best TPU Filament for Flexible, Grippy Prints (2026)
Warping
Warping is corners or edges lifting off the bed as plastic cools and shrinks unevenly, common with ABS printed without an enclosure.
Read more about warpingRelated: Best Enclosed 3D Printers for ABS and Clean Prints (2026)
Wet filament
Wet filament has absorbed moisture from the air, causing popping sounds, tiny bubbles and weaker, rougher looking prints.
Read more about wet filamentRelated: Best Filament Dry Boxes for Moisture-Free Prints (2026)
Z-offset
Z-offset is the fine adjustment between where the printer thinks the bed is and where the nozzle actually touches it.
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