Yes, that is pretty much exactly what I mean. It's an old animation term.
Flash uses it for their path movement and motion tweening and stuff. Back in the day it* was done as a simple percent like so:
In 50%, Out 0% = Object starts slow, gets to full speed at the halfway point, and stops at full speed
In 25%, Out 25% = Object starts slow, gets to full speed 1/4 the way through the path, begins slowing 3/4 the way through the path, and ends slow.
I'm sure you get what I mean even without the examples, I'm just making sure
*(I say back in the day because Flash apparently has these fancy graphs
for creating your ease in/out settings now)