Denshi Jisho — Online Japanese dictionary

姥 うば 1: elderly woman;
2: noh mask of an old woman
Noun 
姥魚 うばうお Aspasma minima (species of clingfish)
Noun, Usually written using kana alone 
姥貝 うばがい Sakhalin surf clam (Pseudocardium sachalinense)
Noun, Usually written using kana alone 
姥鮫 うばざめ basking shark (Cetorhinus maximus)
Noun, Usually written using kana alone 
姥捨て うばすて practice of abandoning old women (practise)
Noun 
姥桜 うばざくら faded beauty
Noun 
姥彼岸 うばひがん double weeping rosebud cherry (Prunus pendula)
Noun, Usually written using kana alone, Obscure term 
姥目樫 うばめがし ubame oak (Quercus phillyraeoides)
Noun, Usually written using kana alone 
姥捨て山 うばすてやま mountain where old women were abandoned
Noun 
姥烏帽子貝 おばえぼしがい Inversidens brandti (species of freshwater mussel)
Noun, Usually written using kana alone 

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