Hmmm ... when I hear "tobacco bloom" referenced, I initially think of those pink and white flowers that emerge from the bud of a maturing tobacco plant. :lol:
I've heard "plume" and "bloom" used with implicit interchangeability for decades in both cigar and pipe discussions. Though I have no horses in this particular race, my time-ravaged brain gravitates towards aligning with the description of material formations from crystalline nucleation as "plume." (Merriam-Webster
does include "a delicate powdery coating on some fruits and leaves" in its definition of "bloom.") Parallel evolution occurs in language, folks.
I've got a big jar of MacBaren Club Blend covered with the stuff. :
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