沦 is typically used in formal or literary contexts and often appears in compounds like 沦陷 (to fall/be captured), 沦落 (to sink into destitution), and 沦为 (to be reduced to).
Three-drop water radical anchors the central image: sinking into water. 沦 literally meant 'ripples spreading on the surface' and 'water swallowing something under'; the modern senses of falling into ruin or degradation grow from that drowning metaphor.
Right side supplies the sound: lún → lún (exact match). 仑 is the simplified form of 侖, a phonetic that anchors a whole family - 论 discuss, 轮 wheel, 伦 ethics, 沦 sink - all sharing the lún reading.
