(computing) regular expression

(elementary mathematics) word problem

(colloquial) current boyfriend

(poetry) a 詞書 (kotobagaki, “explanatory note”) stating that the topic, theme, or occasion of a selected waka poem is unknown; also, the poem with the unknown topic, theme, or occasion

everything

topic or theme of a poem

evaluation / title

evaluate

(slang) Alternative form of 彼氏 (kareshi, “boyfriend”)

everyone, one and all