Complex sentence: Metalloids are sometimes called semimetals, a practice that has been discouraged; the term "semimetal" has a different meaning in physics, that more specifically refers to the electronic band structure of a substance rather than the overall classification of a chemical element.
Split into simpler sentences: Metalloids are sometimes called semimetals, a practice that has been discouraged. This is because the term "semimetal" has a different meaning in physics, one that more specifically refers to the electronic band structure of a substance rather than the overall classification of a chemical element.