鯔背[inase] gallant
違背[ihai] violation
棄背[kihai] giving up and turning back
向背[kouhai] one's attitude
上背[uwazei] stature

側背[sokuhai] flank
団栗の背比べ[dongurinoseikurabe] having no outstanding characteristics
中肉中背[chuunikuchuuzei] medium build
中背[chuuzei] average height
二律背反[niritsuhaihan] antinomy

御馳走様でした[gochisousamadeshita] That was a delicious meal (said after meals)
一っ走り[hitoppashiri] spin (as in 'take a car for a spin')
一走り[hitohashiri] spin
逸走[issou] escape
駅伝競走[ekidenkyousou] long-distance relay race

快走[kaisou] fast sailing (running)
滑走[kassou] glide
滑走路[kassouro] runway
完走[kansou] running the race
競走[kyousou] race