縱

It is a phono-semantic compound, composed of:

糸 (silk, thread) – semantic element, indicating linear extension or threads;

從 (jong, “to follow, to comply”) – phonetic element.

The imagery is of threads running lengthwise, which developed into the sense of vertical direction, extension, and free movement.

In Korean, 종 (縱) is used in contexts of verticality, extension, or indulgence:

세로종 (縱) – vertical, lengthwise

纵横 (종횡, 縱橫) – vertical and horizontal, in all directions

방종 (放縱) – self-indulgence, licentiousness

종용 (縱容) – indulgence, connivance, tolerance

종축 (縱軸) – vertical axis (opposite of 횡축 橫軸)