のんびり屋 - easygoing person
Nice word indeed! I’ve seen the other meanings, really versatile word. My very first reading was きょくしゃ, which wouldn’t work. Then I remembered that, for people doing “bad” things, ‘者’ is usually read ‘もの’, and saw that another possible writing for the word, though rarely used, is ‘癖者’. 
八つ（やっつ）eight
爪切り (つめきり) = Nail Clippers.
リストラ (corporate) restructuring, downsizing, laying off people
ライトノベル = Light novel
類似 - similarity
痔 - hemorrhoid!!!
人口（じんこう）population
脹脛 （ふくらはぎ）（calf of leg)
I think you meant こむら (腓), which is also ‘calf (of the leg)’.
If this is so, 次の言葉は… ら抜き言葉 (らぬきことば) - dropping the ‘ら’ in the potential form of verbs formed with ‘られる’. See here for more information.
爆発 (ばくはつ) = Explosion.
つばめ swallow
滅亡(めつぼう) downfall
貿易 (ぼうえき) = Trade (As in International Trading).
機能（きのう）functions
馬（うま）horse
万が一 (まんがいち) = 1 in 10,000/Very Unlikely.
右翼(うよく) right wing politics
果物籠 - fruit basket 
Such a nice word, 四字熟語 and all of the kanjis with the same demon radical (鬼)! すごいですね!
