Okay, maybe not completely

Before we get started: don't actually ban your dev team from using these words. Ban them from the behaviors associated with these words and your dev team will communicate more effectively, get along better, and produce higher quality products.

"Just"

You've probably heard this one before:

"We'll just use this library."

Or maybe this one?

"It's just a small feature."

And especially this one:

"Can we just do it this way?"

These are all forms of dismissing complexity. Hearing your team say things like this should be a big red flag: it's a sign that they're not taking in to account hidden complexity. Encourage them to take the time to slow down and carefully analyze even seemingly simple tasks. Have them conduct a "pre-mortem" to figure out what can go wrong ahead of time.

"No"

How many times have you asked a developer...

"Can we add functionality X to feature Y?"

...only to hear a flat "no" as a response? It's frustrating, but there is an easy way to prevent it. Rather than asking if you "can" do something, ask this:

"How much effort is it to add functionality X to feature Y?"

This reframes the conversation and allows the developer to give a more nuanced answer. After all, the conversation isn't about whether it's possible to do something, it's about whether the time and effort is worth the payoff.

"Fault"

This one is toxic to your team dynamic. Here's what it sounds like:

"We didn't finish everything because Frank took too long."

"Sales sold something we can't possibly deliver."

"The code was fine, it's the devops team's fault."

"The servers are fine, it's bad app code that's the problem."

There's a common theme with all of these: they're instances of pointing fingers at problems rather than offering solutions. You must, at all costs, root out and destroy any "us vs. them" behavior in your team! Remind everyone that you're all in this together and that failure is everyone's fault.