Yes off course spreading baseless rumours or lies are a form of bullying, because those activities are harmful or those activities are carried out with the intention of causing HURT...

Maybe the underlying CAUSE of the bullying could jealousy or insecurity but the actions are bully tactics (to cause hurt because I can, because I'm bigger or richer or because I don't like you or whatever)...

As @Duttoneer points out, "attack / slam / insult" those are bully tactics...

Sometimes you may join a social website, where there's an elite group who maintain control over conversations by grouping together and diminishing the value of newcomers comments or posts, labelling them as whacko's, simply because the newcomers ideas/posts doesn't fit the groups clique... And maybe these group actions could been seen as bullying too...

Conversing with someone or each other (as we are doing now) and debating things / points, without insult or denigrating anyone is NOT bullying obviously... After all everyone has a right to an opinion, no matter how accurate or out of whack it may be...

A recent case that (I would say) outlines all the hallmarks of bullying...

And the consequences of it, if it is not caught and the perpetrator is not "rehabilitated" or the perpetrator does not "grow out of it"..

Then the bullies moves onto bigger things" (like the horrific recent case) such as even murder...

https://en.wikipedia.org/wiki/Murder_of_Brianna_Ghey

What ever happened to "sticks and stones"?

We should all be bubble boys and girls and this society will never ever ever get hurt