I am seeking "quotable equivalents" for MA (Martin's axiom). For the continuum hypothesis, examples of such statements are as follows.

(a) (Sierpinski) The (xy) plane can be covered by countably many $x \mapsto y$ and $y \mapsto x$ functions.

(b) (Zoli) The set of transcendental reals is a union of countably many transcendence bases for $\mathbb{R}$.

(c) (Erdős) There is an uncountable family of analytic functions on $\mathbb{C}$ that takes only countably many values at each complex number.

(d) (Freiling) There is a function $F$ from $\mathbb{R}$ to the family of countable subsets of $\mathbb{R}$ such that for every $x, y \in \mathbb{R}$, either $x \in F(y)$ or $y \in F(x)$.

Since each one of (a)-(d) refers to a "countable/uncountable" dichotomy, it would be reasonable to have statements with a "continuum/smaller than continuum" dichotomy.