ミドル級[midorukyuu] middleweight class
一級[ikkyuu] one grade
下級[kakyuu] lower grade
下級職[kakyuushoku] subordinate post
下級審[kakyuushin] lower court

下級生[kakyuusei] underclassmen
下層階級[kasoukaikyuu] proletariat
仮進級[karishinkyuu] conditional promotion
階級[kaikyuu] (social) class
階級章[kaikyuushou] rank insignia

グリーン車[guriinsha] green car (1st class)
愛車[aisha] (one's) beloved car
医療車[iryousha] clinic car
井戸車[idoguruma] well pulley
１等車[ittousha] first-class carriage (coach)

一輪車[ichirinsha] unicycle
横車[yokoguruma] perverseness
下り列車[kudariressha] trains going away from the capital
下車[gesha] alighting (from train, bus, etc.)
火の車[hinokuruma] fiery chariot (which carries the souls of sinners into hell)

高が[takaga] it's only ... (something)
意気軒高[ikikenkou] in high spirits
異常高温[ijoukouon] abnormally high temperatures
一斉高[isseidaka] all-round (market) advance
雲高[unkou] height of clouds

円高[endaka] high-valued yen
価値高い[kachitakai] valuable
可能性が高い[kanouseigatakai] very likely
勘定高い[kanjoudakai] calculating
気高い[kedakai] sublime