Denshi Jisho — Online Japanese dictionary

ある a certain ...; some ...
Common word, Pre-noun adjectival, Usually written using kana alone 
ある a certain ...; some ...
Pre-noun adjectival, Usually written using kana alone 
あるは or; possibly
Irregular okurigana usage, Adverb, Conjunction, Expression, Usually written using kana alone 
あるひ one day (e.g. "one day while studying, ..")
Irregular okurigana usage, Noun 
る日 あるひ one day (e.g. "one day while studying, ..")
Noun 
あるい or; possibly
Irregular okurigana usage, Adverb, Conjunction, Expression, Usually written using kana alone 
いは あるい or; possibly
Common word, Adverb, Conjunction, Expression, Usually written using kana alone 
る種 あるしゅ certain; some kind of; some sort of; of sorts
No-adjective 
る時 あるとき once (i.e. "once, when I was studying ..")
Noun 
る人 あるひと someone (unspecified, but someone in particular); a certain person
Noun 
る程度 あるていど to some extent; to a certain extent
Expression, No-adjective, Adverb 
ある意味で あるいみで in a sense; in some way; to an extent
Common word, Expression 
ある意味では あるいみでは in a sense; in some way; to an extent
Common word, Expression 
る程度まで あるていどまで to some degree; up to a point; to some extent
Expression 

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