Usain Bolt and GF Reveal Baby Daughter's Name, Olympia Lightning Bolt!!!

Olympics legend Usain Bolt and his girlfriend, Kasi Bennett, have revealed the name of their baby daughter ... and it may be the most perfect name EVER!!!

Olympia Lightning Bolt.

Come on, does it get any better than THAT?!?!

Baby Bolt was born back on May 17 -- but the couple decided to finally go public with the name on Tuesday while celebrating Kasi's 31st birthday.

In an emotional bday IG post to Kasi, Usain wrote ... "I want nothing but happiness for u and will continue to doing my best keeping a smile on ur face."

"Now we have started a new chapter together with our daughter Olympia Lightning Bolt I look forward to what the future will bring for us but be reassured that I will be the ROCK for this family."

33-year-old Bolt and Bennett have been together for about 7 years now ... and the sprinter had previously shared his excitement about becoming a #GirlDad.

Congrats!!! And, welcome to the world, Olympia!!

Also, CAN YOU IMAGINE IF SHE BECOMES A SPRINTER AND COMPETES IN THE OLYMPICS!

OLYMPIA LIGHTNING BOLT FOR THE WIN!!!