北極光

ほっきょくこう きたきょっこう

northern lights, aurora borealis

南極光

なんきょくこう

aurora australis, southern lights

光陰極

こういんきょく

photocathode

極極

ごくごく

extremely, highly

冷陰極蛍光管

れいいんきょくけいこうかん

Cold cathode fluorescent lamp

極

ごく きょく

climax, extreme, extremity, culmination, height, zenith, nadir

極楽極楽

ごくらくごくらく

It's absolute heaven, It's sheer bliss

光

ひかり

light

極意

ごくい

deepest level (of an art, skill, etc.), secret teachings, mysteries, innermost secrets, the secret (of success, etc.)

極暑

ごくしょ ごく しょ

intense heat, hottest season, peak of summer's heat

太極

たいきょく

taiji (in Chinese philosophy, the principle that embodies all potential things, incl. time and space)

極月

ごくげつ

last month of the year, December

極太

ごくぶと

very thick, something extremely thick

寒極

かんきょく さむごく

a place of extreme cold

極量

きょくりょう

maximum dose

極論

きょくろん

extreme logic, extreme argument, unreserved argument

極左

きょくさ

extreme left, ultraleft

極流

きょくりゅう

polar current

極希

ごくまれ

extremely rare