You can think of clump as one thick shapeless mass made of things that have pressed together: a handful of wet earth, hair stuck in a drain, a few bushes grown into one dark shape. Nothing in it is arranged, and nobody lined it up. The parts simply hold together, and you see the mass before you see the parts.
From the word’s history
Wiktionary traces clump to Middle English clompe and Old English clymppe, a variant of clympre meaning a lump or mass of metal, from Proto-Germanic *klumpo, mass or lump. The oldest recorded meaning is already the lump itself.
Wiktionary 把 clump 追到中古英語 clompe、古英語 clymppe，它是 clympre（一團金屬）的變體，再往上是原始日耳曼語的 *klumpô（團、塊）。所以「一團東西」這個畫面，從最早的紀錄就已經在了，不是後來才長出來的。
Wiktionary entry for clump (evidence packet source_ref kaikki:3f6f69a190036ae4:1019805917:14005)
登入就可以看每一支怎麼連回核心畫面。