UL
In computing and internet slang, UL means to upload — the reverse of DL (download).
Etymology timeline
Born ~1990 · no dated citations yetDefinitions
In computing and internet slang, UL means to upload — the reverse of DL (download). It's been part of tech and file-sharing communities since the dial-up era, appearing on forums, FTP sites, and peer-to-peer networks where every byte of bandwidth mattered. Separately, UL also refers to Underwriters Laboratories, the US product-safety testing organization whose seal appears on electrical devices. Context tells you which one you're dealing with.
Comments
(computing) To upload.
Comments
(US) , a product-safety testing laboratory.
Comments
Have a better definition?
Add your own interpretation of "UL".
⚡About Tech, Dev & AI slang
The vocabulary of software engineers, AI researchers, and anyone living in a terminal or on GitHub — from LLM to MCP, CORS to vibe coding, agentic to enshittification.
See all Tech, Dev & AI slang on Slangora.
Tags
Other words near "UL" (U)
Browse all slang words starting with U.
Related terms
People also read
Semantically related
- ULC62%
(Canada, standards, products, testing) , a product-safety testing laboratory.
- recognized component61%
(US, insurance, business) An item to be used as a subcomponent and tested for safety by Underwriters Laboratories ("UL"); the item will have a special trademark of UL.
- ult60%
Short for "ultimate." A character's signature, long-cooldown ability in any MOBA or hero-shooter. "Ult up" = your ultimate is ready. "No ult" = terrifying. Team fights are often decided by whose ults are off cooldown — "save your ult" is shouted into every voice channel.