her ‧ met ‧ ic ‧ ally /həˈmetɪkli $ hər-/ BrE AmE adverb technical
[ Date: 1600-1700 ; Language: Modern Latin ; Origin: hermeticus , from Hermes Trismegistus, a magician in ancient stories who invented a way of keeping air out of containers ]
hermetically sealed very tightly closed so that air cannot get in or out SYN airtight
—hermetic adjective