Appropriate terminology for classifying some assumptions

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I would like your help in order to choose the appropriate terminology for classifying the assumptions below.

Consider a random vector $X\equiv (X_1,X_2,X_3)$.

Let $\Delta X\equiv (X_1-X_3, X_2-X_3, X_1-X_2)$ with probability distribution denoted by $P_{\Delta X}$ whose marginals are $(P_{\Delta X})_k$ for $k\in \{1,2,3\}$.

Take the following possible assumptions on $P_{\Delta X}$:

(1) $(P_{\Delta X})_1=(P_{\Delta X})_2=(P_{\Delta X})_3$

(2) $(P_{\Delta X})_k$ has median zero $\forall k\in \{1,2,3\}$

(3) $(P_{\Delta X})_k$ is symmetric around zero $\forall k\in \{1,2,3\}$

Assumptions (1), (2), (3) are all implications of assuming

(4) $\{X_1,X_2,X_3\}$ are exchangeable.


Question: I would like your help to find a generic and common way to refer to assumptions (1), (2), (3).

At the moment I thought about

"(1), (2), (3) are assumptions imposing various degrees of symmetry on $P_{\Delta X}$"

motivated by the fact that (1), (2), (3) are implications of exchangeability which is indeed an assumption of symmetry. However, I don't like this taxonomy very much because of the word "symmetry" which may confuse the reader since it appears also in (3).

Also, I don't want to explicitly mention the fact that (1), (2), (3) are implications of exchangeability, such as something like

"(1), (2), (3) are different implications of exchangeability"

Any better suggestion?