What is a nonmetal in physics?

[RENE_VERNON]

I’d've thought that in physics a nonmetal would be a semiconductor or an insulator.

However use of the term "nonmetal" in physics does not appear to be well established.

Here's an extract from Fundamentals of Physics (Halliday, Resnick & Walker 2005, 7th ed., p. 563):

We can classify materials generally according to the ability of charge to move through them. Conductors are materials through which charge can move rather freely; examples include metals (such as copper in common lamp wire), the human body, and tap water. Nonconductors—also called insulators—are materials through which charge cannot move freely; examples include rubber (such as the insulation on common lamp wire), plastic, glass, and chemically pure water. Semiconductors are materials that are intermediate between conductors and insulators. 

Nowhere in this 1,248-page source are any of the terms nonmetal/s; non-metal/s; nonmetallic; or non-metallic used.

To my surprise, the Oxford Dictionary of Physics, 8th ed. (2019) defines "nonmetal" in the same way as set out in the Oxford Dictionary of Chemistry, 8th ed. (2020):

An element that is not a metal. Nonmetals can either be insulators or semiconductors. At low temperatures nonmetals are poor conductors of both electricity and heat as few free electrons move through the material. If the conduction band is near to the valence band (see energy bands) it is possible for nonmetals to conduct electricity at high temperatures but, in contrast to metals, the conductivity increases with increasing temperature. Nonmetals are electronegative elements, such as carbon, nitrogen, oxygen, phosphorus, sulphur, and the halogens. They form compounds that contain negative ions or covalent bonds. Their oxides are either neutral or acidic. 

Do physicists seemingly have no independent conception of what a nonmetal is?

[duane78]

It seems that the term "nonmetal" indeed doesn't have a well-established, standalone definition in physics, as it does in chemistry. Instead, physicists tend to classify materials based on their electrical properties, categorizing them as conductors, insulators, or semiconductors.

[prestigespencer]

It appears that unlike in chemistry, the term "nonmetal" in physics lacks a clear, independent definition. Rather than this, materials are typically categorized by physicists according to their electrical characteristics, which include conductors, insulators, and semiconductors. Prestige Spencer Heights Hyderabad

[niklonjoey756]

In physics, a nonmetal is a type of material protrans tracking number that does not exhibit the characteristics of metals, such as:

- Conducting electricity
- Malleability
- Ductility
- High thermal conductivity

Nonmetals are typically:

- Insulators or poor conductors of electricity
- Brittle or non-malleable
- Low in thermal conductivity

Examples of nonmetals include:

- Carbon
- Nitrogen
- Oxygen
- Phosphorus
- Sulfur

[Allan_pottss]

In physics, nonmetal isn't commonly used; instead, materials are classified by their electrical properties conductors, insulators, and semiconductors. This approach is why terms like nonmetal aren’t typically found in physics texts. However, dictionaries like the Oxford Dictionary of Physics do define nonmetals as elements with poor conductivity at low temperatures, aligning with chemistry. While physicists don’t often use the term, the characteristics of nonmetals like their role as insulators or semiconductors are still relevant to understanding material properties.

[AllanNawyer]

It's true that in physics, the term "nonmetal" isn't as widely or clearly defined as it is in chemistry. Physicists often focus more on the electrical properties of materials—such as conductors, semiconductors, and insulators—rather than categorizing them as metals or nonmetals. While nonmetals in chemistry are typically defined by their inability to conduct electricity and heat well, their role in physics revolves around their behavior in different states and how their atomic structures interact under various conditions. Interestingly, resources like reddy anna online are similar in this way they adopt a broad and flexible approach to various domains, integrating multiple perspectives to provide a more holistic understanding, much like how different scientific disciplines sometimes approach the same concept from varying angles.