Skip to main content
Dictionary
Store
Blog
World
Help
Advertise
Chat
System Status
Information Collection Notice
Trademark Concerns
reCAPTCHA Privacy
Terms of Service
reCAPTCHA Terms
Privacy Policy
Accessibility
Report a Bug
Data Request
Contact Us
Security
DMCA
© 1999–2026 Urban Dictionary ®
Mugs
Tees
Hoodies
Pro Customization
Create unique products with your own words and definitions
Preview
Personalize Your Design
Your Word
Your Definition
A theoretical framework extending general relativity and cosmology by proposing that spacetime has more than the familiar three spatial and one temporal dimension—potentially 5, 10, or 26 dimensions, depending on the model. These extra dimensions may be compactified (curled up at microscopic scales) or large but hidden, explaining why we don’t perceive them in everyday life. The theory is central to string theory and M‑theory, where additional dimensions allow the unification of gravity with quantum mechanics. It also has implications for cosmology (why the universe expands), particle physics (why masses have specific values), and speculative possibilities like wormholes or time travel.
Text fits
Save
Cancel