molder

Molder, or moulder in British English, has several related meanings in English. As a noun, a molder is a person who makes or uses molds to shape materials. In industrial settings, a molder may specifically refer to someone who creates sand or other molds for metal casting, plastics, or ceramics. A molder is often responsible for preparing mold components, assembling cores, applying release agents, and ensuring that molded parts meet dimensional tolerances.

As a verb, to mold (or to moulder) means to shape or form something in a mold, or to influence the development of someone or something. In manufacturing, molding refers to the process of forming a material by introducing it into a mold cavity and allowing it to set or cure, with methods such as injection molding, compression molding, blow molding, and rotational molding. In a broader sense, the phrase “to mold a character” is commonly used.

A different, non-fabrication sense is historical: to molder means to decay or rot gradually. This sense is distinct from the fabrication sense of molding and is commonly used in reference to objects or buildings that are deteriorating over time. The noun mold (or mould) can also refer to the growth of fungi, which is a separate usage from the shaping processes described above.

Etymology traces to mold/mould, with the agent-noun suffix -er/-our forming occupational terms; spelling varies by region: American English favors molder, British English favors moulder.