Denshi Jisho — Online Japanese dictionary

得意 とくい 1: triumph; prosperity;
2: pride;
3: one's strong point; one's forte; one's specialty;
4: frequent customer (client, etc.)
Common word, Noun, No-adjective, Na-adjective 
得意げ とくいげ triumphant; exalted
Adverb, Na-adjective 
得意気 とくいげ proud; elated
Na-adjective, Noun 
得意場 とくいば customer; client
Noun 
得意先 とくいさき customer; client; patron; clientele; constituency
Common word, Noun 
得意顔 とくいがお triumphant look
Noun 
得意技 とくいわざ signature move (assoc. with a martial artist, wrestler, etc.); finishing move
Noun, Martial arts term 
得意がる とくいがる to be inflated with pride
Godan verb with ru ending 
得意四つ とくいよつ sumo wrestler's favourite (favorite) grip on the belt
Noun 
得意客 とくいきゃく customer; client; one's customers
Noun 
得意分野 とくいぶんや one's field of expertise
Noun 
得意淡然 とくいたんぜん not letting oneself puffed up by one's success; maintaining a serene state of mind when one has achieved a great success
Usually written using kanji alone, Taru-adjective, Adverb taking the 'to' particle, Archaism 
得意満面 とくいまんめん triumphant air
Na-adjective, Noun, No-adjective 

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