To save this word, you'll need to log in.
Definition of lifeline
1 : a line (such as a rope) used for saving or preserving life: such as
a : a line along the outer edge of the deck of a boat or ship
b : a line used to keep contact with a person (such as a diver or astronaut) in a dangerous or potentially dangerous situation
2 : something regarded as indispensable for the maintaining or protection of life
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Test Your Vocabulary
Semantic Drift Quiz
- Which of the following was once a synonym for fun?

Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
Share lifeline
Time Traveler for lifeline
The first known use of lifeline was in 1700
See more words from the same year