A phrase commonly used by the fandom side of the social media website tumblr to describe a reaction of an inhuman noise (that sounds like a pterodactylscreech) one has made after they see something that pleases them greatly and instantly excites them.
UwU speech, also known as verbal diabetes, is the complete saturation of language with sweet and cutewords, and or the replacement/repetition of letters within words with other letters to accentuate the childish and sweet tone, often the letter "w" being ruthlessly abused. Emoticons/Emoji usage may vary but if used generally serve to exaggerate the coma inducing sweetness.
Examples of UwU speech
1. "Hewwo Daniel, w-would you liek sum snuzzles? :3 <3 uwu"
2. ">~< thancc you honeycookie. (insert anime emoji with hearts) i twied me best <<3. "
Synonymous with 'Gay Panic', defined as the high-pitched voice-cracking screech a gay produces when they're in a fit of chaotic gay panic. Usually when their gay beliefs (such as a gay believing they're top, twink, daddy etc.) are being questioned. Or when someone attractive tells them something nice and/or flirty.
A hoe you call best friend: "When Craig picked you up after you tripped like a drunk bitch and asked you if you were fine, I swear I saw you blush. Are you a bottom?"
You: "*gay screech* I SWEAR I'M A TOP, A TOP I SAY"