Quarantine is enforced isolation used specifically to stop a disease spreading, often for a set period, while isolation is the broader, general state of being separated from others. A memory hook: quarantine comes from the Italian word for about forty, after the forty-day wait imposed on ships arriving in Venice during plague outbreaks.
The core difference
Quarantine is a specific, disease-prevention form of separation, while isolation is the more general word for being kept apart.
- quarantine — enforced isolation to stop a disease spreading: Travelers arriving from the outbreak zone were placed in quarantine for two weeks.
- isolation — the state of being separated or apart from others: He spent the winter in near-total isolation at the remote cabin.
- isolation — also used in science for separating one factor from everything else: The isolation of the virus was a key step in developing the vaccine.
How to tell them apart
Quarantine has a built-in sense of time and origin: it comes from the Italian quarantina, about forty, after the forty-day period ships were once held in isolation off Venice during plague outbreaks. That history is baked into the word, even though modern quarantine periods vary.
Isolation, by contrast, is the general term. It covers anything from a person living apart from others to a scientist isolating a virus in a lab, and it does not carry quarantine's specific disease-control history or fixed-period sense.
