Why does speech recognition take up 1 GB or RAM suddenly? And Gmail in Safari 738 MB?

You can kill this process (in terminal or activity monitor), and it seems as long as the Dictation & Speech pref pane (Yosemite) has dictation and enhanced dictation off and the pref pane is not open, it won't re-spawn.

See for ref:

http://www.mcelhearn.com/os-x-10-9-mavericks-enhanced-dictation-is-a-memory-hog-and-doesnt-work-very-well/

https://discussions.apple.com/thread/5824504

I've found that the speech recognition services do not load by default. The first time you hit the hotkey (which on my machine is hitting Fn twice), it loads the ~1GB of service into RAM.

Unless you've unwittingly hit the hot key or activated some software that wants to use voice recognition, it shouldn't be loaded. That being said, if you don't want to use speech recognition, you could check the box to disable enhanced recognition and only consume ~18MB of RAM. The non-enhanced recognition action is that it samples your voice and sends it to Apple's servers (obviously creating limits and non-realtime feedback). The enhanced flag just loads those libraries on your Mac locally and avoids going to Apple's servers.

I had to "force quit" it two or three times before I finally got rid of it. I thought 16 GB was a lot of memory, but was surprised to see how many processes are running even when I only have two apps running.