(ecology) Allee effect

effective

synergy

skin effect (tendency of alternating current to distribute itself)

100-yen shop, a common type of Japanese shop similar to dollar store or pound shop, where everything is sold at 100 yen.

七七日: the forty-ninth day after a person dies; the Buddhist memorial service that occurs forty-nine days after a person dies

(onomatopoeia, slang) sexy

日日: day by day

日日: every day, daily

乳: milk; breast; latex (milky substance in plants) / 父: one's own father; a father figure; the Christian God / 致知: the pursuit of knowledge; / 遅遅, 遅々: slowness, tardiness; a long day