English Reference

Word

solder

Phoneticssol·der

US/ˈsɑdɝ/

UK/sˈɒldɐ/

Definitions

01metal alloy

B2 · Technical

n. a soft metal that melts easily, used to join wires or metal parts together.

n. a fusible metal alloy, traditionally composed of tin and lead, used to create a permanent bond between metal workpieces.

“He used a small amount of solder to fix the broken wire on the circuit board.”

“The technician applied the solder precisely to the joint, ensuring a reliable electrical connection without damaging the surrounding components.”

Technical

Synonyms

alloyfiller metal

02to join with metal

B2 · Technical

v. to join two pieces of metal by melting a soft metal onto them.

v. to join or mend metal objects by applying a molten alloy with a lower melting point than the workpieces.

“You need to solder these two wires together to complete the circuit.”

“After cleaning the copper pipes, the plumber began to solder the joints to prevent any future leaks in the system.”

Technical

Usage

The verb is transitive and requires a direct object, often the parts being joined.

Synonyms

Antonyms

desolderdetach

03to bond strongly

C1

v. to join two things or people together very strongly, like they are one piece.

v. to unite or bond things or people closely and firmly as if by the use of solder.

“The shared experience of the war helped solder the two nations together.”

“Years of collaborative research had served to solder their professional relationship into a formidable partnership that dominated the field.”

Literary

Synonyms

Antonyms

Real-World Examples

“I’d never done it before, but the seven-segment display had to be soldered to its backpack board, so I grabbed a baby’s-first-soldering-iron kit from Amazon and a roll of 60/40 solder.”
Ars Technica · 23 Jul 2026

Etymology

From Middle English souder, soudere, soudur (noun), from Old French soldure, soudeure (noun), from Old French souder, solder (“to solder”, verb) (> Middle English souden (“to solder”)), from Latin solidāre (“make solid”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Related words

This entry

Level
C1 · Advanced
Frequency
Occasional
Updated

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