What does weld mean?
Weld is chiefly a verb meaning to join pieces of metal or hard plastic by heating them, often while applying pressure and, in metalworking, sometimes a separate filler material. The resulting permanent junction is also called a weld, particularly at the point where two pieces meet. Outside technical contexts, to weld can mean to unite separate people, organizations, or ideas into a cohesive whole, though the image of two strong pieces becoming one usually remains. Weld has an additional botanical meaning: it names a yellow-flowered plant whose leaves once yielded a vivid yellow dye and which was historically cultivated for that purpose. In British English, the verb may also refer to mending or joining fabric by stitching, a use that is less prominent in American English. The word is therefore both a practical term for a durable joining process and a memorable example of how a single English word can acquire technical, figurative, regional, and historical meanings.
To join pieces of metal or hard plastic by heating them, usually with pressure and sometimes with filler material; more broadly, to unite things so that they form a strong, continuous whole.
"The mechanic welded the two sections of the exhaust pipe."
The verb is common in technical, industrial, and craft contexts. Figurative uses are established, while the British sense of joining fabric by stitching is regional.
A welded joint or the line where two pieces have been joined. The noun also denotes a yellow-flowered plant formerly cultivated for its yellow dye.
"A careful inspection showed that the weld had not been penetrated."
In metalworking, the noun refers to the joint or its joining line. The botanical sense is less frequent and is largely historical outside gardening, dyeing, and botanical contexts.
The plural is used for separate welded joints or joining lines and can also refer to multiple plants of the weld species.
"Pressure tests revealed tiny cracks around several of the welds."
A weld joins metal with heat; the plant called weld was once prized for the vivid yellow dye it produced.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does weld come from?
The technical verb developed in Middle English from Old English forms meaning 'to join' or 'unite'; a Germanic relative, Old Norse velda, means 'to heat' or 'boil.' The modern sense of joining metals by heating developed within metalworking terminology. The botanical noun has a separate history: Middle English wilde continues Old English wilde for the plant and is related to English wild.
Related word forms
How weld is actually used
Weld is common in metalworking, fabrication, and repair, and it is also used for processes that permanently fuse suitable plastics. In British English it can also mean joining or mending fabric by stitching. Figurative uses such as 'weld together' suggest making a strong, lasting union.
Easily confused with weld
A weld is a joint formed by heating and joining metal, whereas a welt is a raised border, strip, or reinforcing edge.