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Start with the full category, then apply the exact boundary: Base units only. Unit names, plurals and symbols are accepted. You only need one qualifying answer. A longer name is not automatically rarer.
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MoleMole is one of the seven SI base units defined by the International Bureau of Weights and Measures.
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CandelaCandela is one of the seven SI base units defined by the International Bureau of Weights and Measures.Aliases: Candelas · cd
98MoleMole is one of the seven SI base units defined by the International Bureau of Weights and Measures.Aliases: Moles · mol
84AmpereAmpere is one of the seven SI base units defined by the International Bureau of Weights and Measures.Aliases: Amperes · Amp · Amps · A
68KelvinKelvin is one of the seven SI base units defined by the International Bureau of Weights and Measures.Aliases: Kelvins · K
63KilogramKilogram is one of the seven SI base units defined by the International Bureau of Weights and Measures.Aliases: Kilograms · kg
30MetreMetre is one of the seven SI base units defined by the International Bureau of Weights and Measures.Aliases: Meter · Metres · Meters · m
25SecondSecond is one of the seven SI base units defined by the International Bureau of Weights and Measures.Aliases: Seconds · s
20Why these answers qualify
Each entry belongs to the bounded set defined by the prompt. The named source supports the underlying facts; our editorial scoring is a separate layer.
Source: BIPM · SI base units
Reference version: 2026-09-13. See our answer policy for how we handle aliases and omissions.