Sister (?), n. [OE. sister, fr. Icel. systir; also suster, from AS. sweostor, sweoster, swuster, akin to OFries. sweester, suster, LG. süster, suster, D. zuster, OS. & OHG. swestar, G. schwester, Icel. systir, Sw. syster, Dan. söster, Goth. swistar, Lith. ses&unr_;, Russ. sestra, Pol. siostra, L. soror, Skr. svasr. √298. Cf. Cousin.] 1. A female who has the same parents with another person, or who has one of them only. In the latter case, she is more definitely called a half sister. The correlative of brother.
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I am the sister of one Claudio. Shak.
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2. A woman who is closely allied to, or assocciated with, another person, as in the sdame faith, society, order, or community. James ii. 15.
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3. One of the same kind, or of the same condition; -- generally used adjectively; as, sister fruits. Pope.
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Sister Block (Naut.), a tackle block having two sheaves, one above the other. -- Sister hooks, a pair of hooks fitted together, the shank of one forming a mousing for the other; -- called also match hook. -- Sister of charity, Sister of mercy. (R. C. Ch.) See under Charity, and Mercy.
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