不悪[ashikarazu] don't get me wrong, but ...
意識不明[ishikifumei] unconscious
一心不乱[isshinfuran] wholeheartedly
一定不変[itteifuhen] invariable
運動不足[undoubusoku] insufficient exercise

栄養不足[eiyoubusoku] malnutrition
過不足[kafusoku] excess or deficiency
回復不可能[kaifukufukanou] non-recoverable
気不味い[kimazui] unpleasant
健康不安[kenkoufuan] poor health

永久歯[eikyuushi] permanent tooth
永久性[eikyuusei] permanency
永久脱毛[eikyuudatsumou] removing hair permanently
久しい[hisashii] long
久しく[hisashiku] for a long time

久し振りに[hisashiburini] after a long time
久し振り[hisashiburi] a long time (since the last time)
久懐[kyuukai] long-cherished hope
久慈目[kujime] spotbelly greenling (Hexagrammos agrammus)
久方[hisakata] sky

アナログデジタル変換器[anarogudejitaruhenkanki] analog-digital converter
パリティ変換[paritihenkan] parity transformation (physics)
異変[ihen] unusual phenomenon
移り変り[utsurikawari] change (e.g. season)
一定不変[itteifuhen] invariable

一風変った[ippuukawatta] eccentric
一変[ippen] complete change
黄変米[ouhenmai] spoiled rice
化学変化[kagakuhenka] chemical change
かな漢字変換[kanakanjihenkan] kana-kanji conversion (on a computer, etc.)

恒温器[kouonki] incubator
恒久[koukyuu] permanent
恒久化[koukyuuka] making permanent
恒常[koujou] constancy
恒心[koushin] steadiness

恒星[kousei] (fixed) star (i.e. not a planet, meteorite, etc.)
恒等式[koutoushiki] identity
恒例[kourei] established practice
恒河沙[gougasha] 10^52 (or 10^56)
恒数[kousuu] a constant (e.g. in science)