御古[ofuru] used article (esp. clothes)
手古摺る[tekozuru] to have much trouble
土耳古[toruko] Turkey
下稽古[shitageiko] rehearsal
懐古[kaiko] recalling the old days

擬古[giko] imitation of classical styles
擬古文[gikobun] classical style
稽古[keiko] practice
遠古登点[wokototen] marks to aid in reading Chinese classics
古え[inishie] antiquity

シュタイナー学校[shutainaagakkou] Steiner school
ビジネススクール入学共通試験[bijinesusukuurunyuugakukyoutsuushiken] business school entrance test
ロボット工学[robottokougaku] robotics
位相幾何学[isoukikagaku] topology
易学[ekigaku] study of divination

遺伝学[idengaku] genetics
遺伝子工学[idenshikougaku] genetic engineering
医化学[ikagaku] medical chemistry
医科大学[ikadaigaku] medical school
医学[igaku] medical science

医界[ikai] medical world
医学界[igakukai] medical world
黄金世界[ougonsekai] utopia
下界[gekai] this world
花柳界[karyuukai] red-light district

界隈[kaiwai] neighborhood
界面[kaimen] interface
各界[kakkai] each field
学界[gakkai] academic or scientific world
官界[kankai] bureaucracy

と考えられる[tokangaerareru] one can think that ...
一考[ikkou] consideration
勘考[kankou] consider
考え[kangae] thinking
考えてみれば[kangaetemireba] if you think about it

考える[kangaeru] to consider
考え込む[kangaekomu] to ponder
考え事[kangaegoto] (deep) thinking
考え出す[kangaedasu] to think out
考え直して[kangaenaoshite] On second thoughts ...