What term describes a vertical column in the periodic table, sometimes referred to as a group?

The term that describes a vertical column in the periodic table is "family." In chemistry, elements that share similar properties are often found in the same vertical column, or family, within the periodic table. These elements typically have the same number of valence electrons, which influences their chemical behavior and reactivity.

For example, the alkali metals (Group 1) and the halogens (Group 17) are families that contain elements with similar characteristics. The grouping helps predict how elements will interact with one another based on their positions on the periodic table.

While "period" refers to horizontal rows in the periodic table, "row" is just a descriptor and does not have the specific chemical implication that "family" does. "Category" is a more general term and isn't commonly used in the context of the periodic table structure. Hence, "family" is the most appropriate term to describe the vertical columns.