naf·​cil·​lin naf-ˈsil-ən How to pronounce nafcillin (audio)
: a semisynthetic penicillin that is resistant to beta-lactamase and is used especially in the form of its hydrated sodium salt C21H21N2NaO5S·H2O as an antibiotic

Dictionary Entries Near nafcillin

Cite this Entry

“Nafcillin.” Medical Dictionary, Merriam-Webster, Accessed 31 Mar. 2023.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Love It or Hate It

  • heart-fire
  • When asked about her blind date, Carol spoke for hours with vitriol.
Spell It

Hear a word and type it out. How many can you get right?

Solve today's spelling word game by finding as many words as you can with using just 7 letters. Longer words score more points.

Can you make 12 words with 7 letters?