Reading
Shortcuts
Home
All Articles
Read from Another Site
Sources
Wikipedia
Simple Wikipedia
VOA Learning English
Futurity
The Conversation
MIT News
Harvard Gazette
Cambridge News
YDS/YÖKDİL Passages
Topics
Technology
Engineering
Business
Economics
Human
Health
Energy
Biology
Nature
Space
Log in
Sign up
History
Add
the back of an envelope
• used in reference to calculations or plans of the most sketchy kind.
• "a proposal drawn up on the back of an envelope"