"vessel used for holding liquids," late 14c., from Medieval Latin phiola, from Latin phiala, from Greek phialē "flat vessel, dish, flat bowl for drinking or sacrificing," a loan-word of unknown origin. It also came to Middle English via Old French fiole "flask, phial" (12c.), hence the diversity of Middle English spellings (fiole,phiole,phial,fial,viole,vial,viele) and modern vial.
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<a href="https://www.etymonline.com/word/vial">Etymology of vial by etymonline</a>
Harper, D. (n.d.). Etymology of vial. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/vial