[xxpor]

A non-managerial role*

If you're a senior IC and you're not exhibiting leadership in some way you're probably not going to be around for very long.

[arnarbi]

You're right, that's what it usually means. But gp was asking about it in the context of this comment: https://news.ycombinator.com/item?id=21377401

Here it's being used to contrast with both TL-ship and management.

[heavenlyhash]

I agree with this and thus often find the term "IC" itself unfortunately prone to being misleading.