Denshi Jisho — Online Japanese dictionary

よう 1: cornerstone; main point; keystone;
2: requirement; need;
3: (Noun or verb acting prenominally) necessary; required
Noun 
いる to need
Common word, Godan verb with ru ending, Intransitive verb 
いり expense; expenses
Noun 
かなめ 1: pivot;
2: vital point; cornerstone; keystone;
3: Japanese photinia
Common word, Noun 
ふよう unnecessary; unneeded
Common word, Na-adjective, Noun, No-adjective 
ようし point; essentials; gist; summary; fundamentals
Common word, Noun 
ようそ 1: component; factor; item (e.g. in list);
2: (Computer terminology) element (e.g. in array); member (e.g. data structure)
Common word, Noun 
ようは in short; the point is
Common word, Adverb 
きよう bulletin; memoirs
Noun 
しよう extremely important
Noun 
ようぎ essence
Noun 
ようぐ necessary tools
Noun 
ようす to need; to require; to take; to demand
Godan verb with su ending, Transitive verb 
ようず outline; rough sketch
Noun 
ようち important place; strategic location
Noun 
ようひ necessary or not; optional (items)
No-adjective 
ようむ important business
Noun 
ようろ 1: main or important road;
2: influential or important position; the authorities
Noun 
らぬ いらぬ needless
Na-adjective 
かんよう essential; vital; crucial; importance
Common word, Na-adjective, Noun, No-adjective 
がいよう outline; summary; abridgment; synopsis
Common word, Temporal noun 
しゅよう chief; main; principal; major
Common word, Na-adjective, Noun 
しょよう required; needed; necessary
Common word, Noun, No-adjective 
じゅよう demand; request
Common word, Noun 
ひつよう 1: necessary; needed; essential; indispensable;
2: (Noun) necessity; need; requirement
Common word, Na-adjective 
ほうよう Buddhist memorial service
Common word, Noun 

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