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head (of a household); proprietor (of a store); proprietress; landlord; landlady; master (of a servant)
「主」 has other readings with different meanings.
主な原因は資金不足だと言われている。
The main cause is said to be lack of funds.
この会社の主な事業は製造業です。
This company's main business is manufacturing.
主として若者向けの製品を作っている。
We mainly make products for young people.