びん首効果 びんくびこうか Also written へいしゅこうか, 瓶首効果 Meanings Noun bottleneck effect See also: ボトルネック効果 (ボトルネックこうか). Kanji 首 neck. Read as くび. 効 effect. Read as コウ. 果 fruit. Read as カ. Jinuma: Japanese Dictionary · Word lists