Exactly what it says on the tin.
Disclaimer: This is not a definitive list. For more meetups check the sources below
AngularJS Melbourne
http://www.meetup.com/AngularJS-Melbourne/
Code Like A Girl
https://www.meetup.com/codelikeagirlau/
DevOps Melbourne
https://www.meetup.com/devops-melbourne/
Elm Melbourne
https://www.meetup.com/Elm-Melbourne/
Elixir Melbourne
https://www.meetup.com/Elixir-Melbourne/
Female Coders Lab
http://www.meetup.com/Female-Coders-Lab-Melbourne/
Free Code Camp Melbourne
https://www.meetup.com/FreeCodeCampMelbourne/
Infrastructure Coders (Infracoders)
https://www.meetup.com/Infrastructure-Coders/
Junior Developers Melbourne
https://www.meetup.com/Junior-Developers-Melbourne/
MelbCSS
Past recordings: YouTube
http://www.meetup.com/MelbCSS/
MelbJS
Past recordings: Vimeo - INACTIVE
http://melbjs.com/
Melbourne Docker User Group
https://www.meetup.com/Melbourne-Docker-User-Group/
Melbourne Node.JS Meetup (MelbNodeJS)
https://www.meetup.com/MelbNodeJS/
Melbourne NodeBots
https://www.meetup.com/Melbourne-NodeBots-Nights/
Random Hacks of Kindness (RHoK)
https://www.meetup.com/Random-Hacks-of-Kindness-Melbourne/
React Melbourne
https://www.meetup.com/React-Melbourne/
Ruby and Rails Melbourne
Past recordings: YouTube
https://www.meetup.com/Ruby-On-Rails-Oceania-Melbourne/
Software Art Thou?
Past recordings: YouTube
https://www.meetup.com/Software-Art-Thou
Tech Brekky
https://www.meetup.com/Tech-Brekky/
The Web Meetup
Past recordings: YouTube
https://www.meetup.com/the-web/