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(v) To intentionally or unintentionally purge the contents of acne on one's back, be it blood or pus. Portmanteau of the words Back (or Bacne) and Lactate.

"Bactation" (n), is the act of Bactating.

See bacne.
The man standing in front of me in line apparently suffered from cystic bacne and clearly began to Bactate through the back of his wolf shirt.
by GrahamBag May 01, 2010