Hi, 1 all 6 : nothing but : only : a : completely taken up with, given to, or absorbed by <became all attention> b : having or seeming to have (some physical feature) in conspicuous excess or prominence <all legs> c : paying full attention with <all ears> [M-W's Col. ] It's a common practice for M-W to first give a main definition, then further sub-definitions underneath. There has to be a connection between "nothing but : only" and "a", "b", and "c".
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