告 means “tell, announce”

こく · koku

Also: revelation, inform

Kun'yomi (Japanese reading)
つげる
On'yomi (Chinese reading)
コク

JLPT N3 · Taught in grade 5 · 7 strokes

The story

A cow (牛) bellowing through an open mouth (口): news nobody can miss. 告 is telling: 報告 is a report, 広告 an advertisement, and 告白, confessing your feelings, is the big scene of many a school romance.

Used in 報告 (houkoku, report), 広告 (koukoku, advertisement), and 告白 (kokuhaku, confession)

More from Ask & Tell

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Readings from KANJIDIC2, © EDRDG, CC BY-SA.