Denshi Jisho — Online Japanese dictionary

おか hill; height; knoll; rising ground
Noun 
おかべ vicinity of a hill
Noun 
おかめ onlooker; bystander
Noun 
おかゆ tank of clean water (in a bath house)
Noun 
おかひき hired thief taker (Edo period); private secret policeman; private detective
Noun, Archaism 
おかぼれ unrequited love; illicit love; secret affections
Noun, Suru verb 
しずおか Shizuoka (city)
Noun 
ふくおか Fukuoka (city)
Noun 
引き おかひき hired thief taker (Edo period); private secret policeman; private detective
Noun, Archaism 
惚れ おかぼれ unrequited love; illicit love; secret affections
Noun, Suru verb 
持ち おかもち wooden carrying box
Noun 
焼き おかやき jealousy; envy
Noun 
おかっぴき hired thief taker (Edo period); private secret policeman; private detective
Noun, Archaism 
こうりょう hill
Noun, Archaism 
場所 おかばしょ red-light district
Noun 
っ引き おかっぴき hired thief taker (Edo period); private secret policeman; private detective
Noun, Archaism 
虎尾 おかとらのお gooseneck loosestrife (Lysimachia clethroides)
Noun, Usually written using kana alone 
宿借 おかやどかり concave land hermit crab (Coenobita cavipes)
Noun, Usually written using kana alone 
山県 おかやまけん Okayama prefecture (Chuugoku area)
Noun 
しずおかけん Shizuoka prefecture (Chuubu area)
Noun 
ふくおかけん Fukuoka prefecture (Kyushu)
Noun 
虎の尾 おかとらのお gooseneck loosestrife (Lysimachia clethroides)
Noun, Usually written using kana alone 
ながおかきょう Japanese capital founded by emperor Kammu in 784, but abandoned 10 years later in favour of Heian
Noun 
裁き おおおかさばき judicial decision made with human kindness and warmth in a fair manner (from the decisions of Oooka Tadasuke, a jurist in 17th century Japan)
Noun 
目八目 おかめはちもく 1: bystander's vantage point; outsider's better grasp of the situation;
2: (Expression) onlookers see more of the game than the players do; lit: people watching a game of Go see 8 moves further ahead
Noun 
ながおかのみやこ Japanese capital founded by emperor Kammu in 784, but abandoned 10 years later in favour of Heian
Noun 
崎フラグメント おかざきフラグメント Okazaki fragment
Noun 
糸魚川静構造線 いといがわしずおかこうぞうせん Itoigawa-Shizuoka Tectonic Line
Noun 

Found 28 words.

You can also

Look up kanji details for *岡*.

Try a Yahoo Jisho search for *岡* .
Try a Goo Jisho search for *岡* .
Try a Google search for *岡* .