The definition of hermetic is something completely sealed or airtight.(adjective)
A container that has been fused shut is an example of a hermetic container.
See hermetic in Webster's New World College Dictionary
Origin: from use in alchemycompletely sealed by fusion, soldering, etc. so as to keep air or gas from getting in or out; airtight
Origin: ModL hermeticus < L Hermes < Gr Hermēs (trismegistos)
See hermetic in American Heritage Dictionary 4
Origin: New Latin hermēticus, alchemical
Origin: , from Medieval Latin Hermēs (Trismegistus); see Hermes Trismegistus.
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