What's considered a plateau?

I think I read somewhere that a plateau is considered to be within a weight range for about 2 weeks or more. I'm curious if I've hit a plateau. Over the last week to week and a half, I've noticed my weight bouncing around a 2 lb range. I do weigh myself daily but it's more for trend tracking purposes. In terms of food intake, meeting macros, etc. it's actually been fairly easy. Throwing in 2-3 HIIT classes a week has helped, of course.

If this is a plateau, here are my random thoughts. Body's getting used to doing 2-3 HIIT classes a week (not sure how anyone can get used to it, hah). I know I have a minor sodium intake issue (please note the sarcasm). 90% of what I drink is water though so hopefully not much of an issue. No heart conditions either.

I'm thinking I need to change things up just a bit. I was looking to throw in a day or two of road running, perhaps a couple of miles each day just to change things up a bit. I do need to cut back on the sodium and carbs a bit, but overall I'm pretty happy with my food journal. Now granted, usually my Monday weigh-ins show the largest weight drop (exercise, chasing 4 yr old, etc) but I'm curious if this is the dreaded wall folks speak of. Thoughts? Thanks!

Wt 7 Day Avg
195.4 197.9
196.0 197.4
194.8 196.7
196.0 196.5
198.0 196.5
195.2 196.1
194.2 195.7
194.4 195.5
193.8 195.2
195.1 195.2