御中[onaka] stomach
御話中[ohanashichuu] busy (phone)
アル中[aruchuu] alcoholism
π中間子[paichuukanshi] pi meson
暗中[anchuu] in the dark

暗中摸索[anchuumosaku] groping in the dark
意中[ichuu] one's mind
意中の女[ichuunoonna] sweetheart
井の中の蛙大海を知らず[inonakanokawazutaikaiwoshirazu] parochial
一日中[ichinichijuu] all day long

ハチ公[hachikou] statue of Hachiko (a dog) at Shibuya station
郭公[kakkou] common cuckoo (Cuculus canorus)
株式公開[kabushikikoukai] stock offering (to the public)
蒲公英[tanpopo] dandelion (esp. species Taraxacum platycarpum)
官公庁[kankouchou] government administration office

丸公[marukou] official price
勤め奉公[tsutomeboukou] apprenticeship
公平[kinpira] chopped burdock root (and sometimes carrot) cooked in sugar and soy sauce
公孫樹[kousonju] ginkgo (Ginkgo biloba)

医務[imu] medical affairs
医務室[imushitsu] doctor's office
外務[gaimu] foreign affairs
外務省[gaimushou] Ministry of Foreign Affairs
外務大臣[gaimudaijin] Minister for Foreign Affairs

義務[gimu] duty
義務教育[gimukyouiku] compulsory education
急務[kyuumu] urgent business
教務[kyoumu] school affairs
業務[gyoumu] business