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Why does the International Union of Pure and Applied Chemistry prefer the term actinoid over actinide?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — actinoid element Modern version of the periodic table of the elements (printable).

The International Union of Pure and Applied Chemistry (IUPAC) prefers the term actinoid over actinide because of established conventions in chemical nomenclature. Specifically, the suffix -ide is typically reserved for negatively charged ions or binary chemical compounds, whereas the term actinoid avoids this potential confusion by using the suffix -oid.12