lecture, club, association
講 centers on organized spoken exchange: a lecture or talk, and by extension a group that meets for such exchange, like a club or association.
講 combines 言 (speech) with 冓, which likely contributes the sound and may relate to an old meaning of 'to meet' or 'to construct', suggesting speech that brings people together.
Words (言) are stacked and arranged like building blocks (冓) to form a lecture. A club or association is where people gather to exchange such structured words.
For コウ, imagine a lecturer using a cone as a megaphone to address the club: cone -> コウ, and the words (言) carry through the cone.
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speaker; lecturer
course (e.g. of lectures)
lecture; address; speech
lecture
short course; training
Kodansha (publisher)
taking a lecture; attending a class; taking a course
(Buddhist) lecture meeting
to lecture; to read aloud; to give a lecture (on)
start of a course; start of lectures
auditorium; lecture hall
to lecture; to read aloud; to give a lecture (on)
reconciliation (between warring nations); (making of) peace
lecture; discourse
storytelling (of war chronicles, revenge tales, etc.) with highly dramatic delivery; story
explanation (of a text, phrase, etc.); lecture; exposition
reading; translation
cancellation (of a lecture, class, etc.)
criticism (by a teacher or coach, with commentary, especially at a poetry reading); review; critique
lecture attendance; auditing