Denshi Jisho — Online Japanese dictionary

空 から emptiness; vacuum; blank
Common word, Noun, No-adjective 
空 そら sky; the heavens
Common word, Noun 
空 うろ hollow; cavity; hole
Noun 
空 くう 1: empty air; sky;
2:
3: (Buddhist term) shunya (emptiness, the lack of an immutable intrinsic nature within any phemomenon);
4: (Abbreviation) air force; () fruitlessness; meaninglessness;
5: void (one of the five elements)
Noun 
空き あき 1: space; room; emptiness; gap;
2: opening; vacancy; empty seat;
3: free time; time to spare;
4: disuse; unused thing
Common word, Noun 
空く あく 1: to open (e.g. doors);
2: to open (e.g. business, etc.);
3: to be empty;
4: to be vacant; to be available; to be free;
5: to be open (e.g. neckline, etc.);
6: to have been opened (of one's eyes, mouth, etc.);
7: to come to an end;
8: () to open (one's eyes, mouth, etc.);
9: () to have a hole; to form a gap; to have an interval (between events)
Common word, Godan verb with ku ending, Intransitive verb 
食う くう 1: (Male term or language) (Vulgar expression or word) to eat;
2: to live; to make a living; to survive;
3: to bite; to sting (as insects do);
4: to tease; to torment; to taunt; to make light of; to make fun of;
5: to encroach on; to eat into; to consume;
6: to defeat a superior; to threaten a position;
7: to consume time and-or resources;
8: (Colloquialism) to receive something (usu. an unfavourable event);
9: (Male term or language) (Vulgar expression or word) to have sexual relations with a woman, esp. for the first time
Common word, Godan verb with u ending, Transitive verb 
空く すく 1: to become less crowded; to thin out; to get empty;
2: to be hungry
Common word, Godan verb with ku ending, Intransitive verb 
啖う くう 1: (Male term or language) (Vulgar expression or word) to eat;
2: to live; to make a living; to survive;
3: to bite; to sting (as insects do);
4: to tease; to torment; to taunt; to make light of; to make fun of;
5: to encroach on; to eat into; to consume;
6: to defeat a superior; to threaten a position;
7: to consume time and-or resources;
8: (Colloquialism) to receive something (usu. an unfavourable event);
9: (Male term or language) (Vulgar expression or word) to have sexual relations with a woman, esp. for the first time
Out-dated kanji, Godan verb with u ending, Transitive verb 
喰う くう 1: (Male term or language) (Vulgar expression or word) to eat;
2: to live; to make a living; to survive;
3: to bite; to sting (as insects do);
4: to tease; to torment; to taunt; to make light of; to make fun of;
5: to encroach on; to eat into; to consume;
6: to defeat a superior; to threaten a position;
7: to consume time and-or resources;
8: (Colloquialism) to receive something (usu. an unfavourable event);
9: (Male term or language) (Vulgar expression or word) to have sexual relations with a woman, esp. for the first time
Godan verb with u ending, Transitive verb 
空地 あきち vacant land
Common word, Noun 
空手 からて 1: karate;
2: empty handed
Common word, Noun 
空気 くうき air; atmosphere
Common word, Noun 
空疎 くうそ vain; groundless; futile
Common word, Na-adjective, Noun 
空母 くうぼ aircraft carrier
Common word, Noun, Abbreviation 
空輸 くうゆ air transport
Common word, Noun, Suru verb, No-adjective 
空路 くうろ air lane
Common word, Adverbial noun, Temporal noun 
空巣 あきす 1: prowler; sneak thief; cat burglar;
2: empty nest
Noun 
空間 あきま vacancy; room for rent or lease
Irregular okurigana usage, Noun, No-adjective 
空家 あきや vacant house; unoccupied house
Noun 
空屋 あきや vacant house; unoccupied house
Noun 
空穂 うつお quiver (of arrows; cylindrical)
Noun 
空木 うつぎ deutzia; Deutzia crenata
Noun 
空け うつけ absentmindedness; dreaminess; simpleton; fool
Noun 
空穂 うつぼ quiver (of arrows; cylindrical)
Noun 
空ろ うつろ blank; cavity; hollow; empty (space)
Na-adjective, Noun 
空荷 からに lacking cargo; in ballast
Noun, No-adjective 

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