一元[ichigen] unitary
一元化[ichigenka] unification
一元的[ichigenteki] monistic
一元論[ichigenron] monism
一次元[ichijigen] one dimensional

一新紀元[isshinkigen] new era
隠元[ingen] beans
隠元豆[ingenmame] common bean (Phaseolus vulgaris)
家元[iemoto] head of a school (of music, dance)
火の元[hinomoto] origin of fire

老麺[raamen] ramen (Chinese-style noodles)
家老[karou] chief retainer
棄老[kirou] old person thrown away in the mountains
敬老[keirou] respect for the aged
敬老の日[keirounohi] Respect-for-the-Aged Day Holiday (third Monday in September)

元老[genrou] elder statesman
元老院[genrouin] (Roman) senate
故老[korou] old people
車海老[kurumaebi] kuruma prawn (Marsupenaeus japonicus)
寿老人[juroujin] god of longevity

医院[iin] doctor's office (surgery)
医院長[iinchou] head doctor
育児院[ikujiin] orphanage
一院制[ichiinsei] unicameral system
院外[ingai] outside congress

院号[ingou] former emperor (or his empress, imperial princesses, etc.)
院政[insei] government by cloistered emperors
院生[insei] graduate student
院宣[inzen] imperial command (decree)
院長[inchou] director