As nouns the difference between weld and weldment

is that weld is a herb (Reseda luteola) related to mignonette, growing in Europe, and to some extent in America, used to make a yellow dye; dyer's broom; dyer's rocket; dyer's weed; wild woad while weldment is a part created from an assembly of smaller components that are joined by welding.

As a proper noun Weld

is {{surname|from=Old English}} possibly deriving from the Old English word for woodland. The family is mainly located in the Southern regions of England.

As a verb weld

is to bind together inseparably; to unite closely or intimately.