apathy

passive, inactive, timid

(dated slang) a woman who is attractive from behind, usually in reference to her buttocks. / (dated slang, in particular) butterface: A woman who is attractive from behind but ugly from the front.

backlash (a strong adverse reaction to a political or social development)

Alternative form of ファストバック (fasutobakku, “fastback”)

Alternative form of クォーターバック (kwōtābakku, “quarterback”)

(American football, Canadian football) a quarterback

(Internet) trackback

backsword

(baseball) backstop