I looked at a couple of definitions of Zionism.
Wikipedia:
> Zionism is an ethnocultural nationalist movement that emerged in late 19th-century Europe to establish and support a Jewish homeland through the colonization of Palestine.
Brittanica:
> Zionism, Jewish nationalist movement with the goal of the creation and support of a Jewish national state in Palestine.
Jewish Vioce for Peace (an Anti-Zionist organization):
> Zionism is a form of Jewish nationalism, and is the primary ideology that drove the establishment of Israel.
> The political ideology of Zionism, regardless of which strain, has resulted in the establishment of a Jewish nation-state in the land of historic Palestine.
https://www.jewishvoiceforpeace.org/resource/zionism/
Jewish center for justice (a Zionist organization):
> Zionism is the belief in the Jewish people’s right to self-determination in our ancestral homeland of Israel.
> Today, supporting Zionism means promoting the continued existence of a Jewish state and upholding the right of Jews to live freely in their historic homeland.
https://jewishcenterforjustice.org/what-is-zionism-six-thing...
Zioness.org (a Zionist publication):
> The progressive movement for liberation and national self-determination of the Jewish people in our indigenous homeland, the land of Israel.
Zack Beauchamp (A journalist and a Liberal Zionist):
> Zionism is Israel’s national ideology. Zionists believe Judaism is a nationality as well as a religion, and that Jews deserve their own state in their ancestral homeland, Israel.
https://www.vox.com/2018/11/20/18080010/zionism-israel-pales...
There is a varying degree in what these definitions call the land in question (Israel; Jewish ancestral homeland; etc.; I just call it Palestine) and where exactly that land is (1967 borders; Israel + occupied territories; Israel + Sinai + Jordan + South Lebanon + ect.). There is also a varying degree of how much rights to grant the indigenous population. Liberal Zionists want to grant them equal rights as a minority, while Kahanists want to expel them again in a Geoncide. But all Zionists agree that Zionism is a national project to maintain a Jewish supremacy state in Palestine.
A liberal Zionist would refute the description Jewish supremacy because in a democratic Israel all citizens should have the same rights. I refute that refutation on the basis that without the right of return for the 1948 refugees, Israel has artificially created a racial majority on lands that did not belong to them, and thus have created a supremacy through majority rule via a violent expulsion of the indigenous population.