Denshi Jisho — Online Japanese dictionary

そばめ mistress; kept woman; concubine
Noun 
めかけ mistress; kept woman; concubine
Noun 
わらわ I; me
Pronoun, No-adjective, Archaism, Humble (kenjougo) language, Female term or language 
おんなめ mistress; kept woman; concubine
Out-dated or obsolete kana, Noun 
あいしょう beloved concubine; favourite concubine (e.g. of the shogun)
Noun 
がいしょう foreigner's mistress
Noun 
さいしょう one's wife and mistress(es)
Noun 
だんしょう male paramour
Noun 
ちくしょう keeping a mistress (concubine)
Noun, Suru verb 
ようしょう Westerner's mistress
Noun 

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