Denshi Jisho — Online Japanese dictionary

ねつ 1: heat;
2: fever; temperature;
3: zeal; passion; enthusiasm;
4: mania; craze; rage
Common word, Noun 
ねす to get a fever
Godan verb with su ending, Intransitive verb, Archaism 
厚い あつい 1: thick; deep; heavy;
2: kind; cordial; hospitable; warm; faithful;
3: abundant
Common word, Adjective 
暑い あつい hot (weather, etc.); warm
Common word, Adjective 
あつい hot (thing)
Common word, Adjective 
ねっき heat; hot air; enthusiasm
Common word, Noun 
ねつい zeal; enthusiasm
Common word, Noun 
篤い あつい 1: kind; cordial; hospitable; warm; faithful;
2: serious (of an illness)
Adjective 
あつさ heat (of a thing)
Noun 
あつめ hot
No-adjective 
あつゆ warmer than usual bath
Noun 
いきれ steamy, very warm temperature
Noun 
ねっさ hot sand
Noun 
ねっぱ heat wave
Noun 
ねつけ feverish
Noun 
ねつど degree of heat; temperature; enthusiasm
Noun 
ほてり 1: a glow; heat;
2: burning sensation; hot flash
Noun, No-adjective 
あつあつ 1: piping hot;
2: passionately in love
Common word, Na-adjective, Noun, No-adjective 
ねっしん zeal; enthusiasm
Common word, Na-adjective, Noun 
ねっせん fierce fighting; close contest
Common word, Noun 
ねったい tropics
Common word, Noun 
ねっとう boiling water
Common word, Noun, No-adjective 
ねつべん fervent speech
Common word, Noun, No-adjective 
ねつれつ ardent; passionate; vehement
Common word, Na-adjective, Noun 
あつあつ 1: piping hot;
2: passionately in love
Na-adjective, Noun, No-adjective 
厚板 あつい plank; thick board; plate glass; heavy metal sheet (esp. welding); heavy brocaded obi
Noun 

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