I'm not sure what you mean by "when boats" exactly it why you used that phrasing, but it seems like an attempt at pre-emptively mocking a strawman, framing it as childish. That's not very nice rhetoric, is it?

These terms are well defined and it would serve you well to simply consult a dictionary.

But in short colonialism implies the use of colonies (surprise surprise) meaning the use of settlers to control or displace populations. There from comes the name

It also differs from other forms of expansionism in a few important ways.

- The power class structure is built on trade imbalances which move resources from the colonised land to the metropole without building up local economies.

- There's no absorption, the territories tend to remain separate and the colonised people can't become citizens or equals with those colonising them.

- And it's understood when speaking about things like the "colonial era" or "historical colonialism" that there was a deal of racial justification and stratification along racial lines.

You'll quickly be able to compare this list to whatever historical event you like.

You can mock the grammar of "only colonialism when boats", but AFAIK when the Soviet Union accused some Western power of engaging in colonialism and got "well, you have your Central Asian dependencies" as an answer, they were quick to refine their definition of "colonialism" to include a "transmaritime" checkbox. So, yeah. FWIW there have been those who accused modern nation states of practicing "internal colonialism" in the sense that oftentimes all the money, support and political representation goes overwhelmingly to some select places while the rest of the country is treated as a convenient reservoir of cheap labor.