used in proper names, (kokuji)
粂 is a kokuji (Japan-made kanji) used almost exclusively in proper names. It has no clear standalone meaning beyond its use in surnames and place names.
粂 is a kokuji created in Japan, combining 久 (long time) and 米 (rice). The exact historical motivation is uncertain, but it likely represents a wish for lasting prosperity or a family name origin.
Picture a family name written with 久 (long time) over 米 (rice), suggesting a lineage that has prospered for ages. The kanji itself is a name, so remember it as a symbol of enduring heritage.
For くめ, imagine a person named Kume who always has a long-lasting (久) supply of rice (米) in their storehouse: Kume -> くめ.
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