Abstract A starrable lattice is one with a cancellative
semigroup structure satisfying $(x\vee y)(x\wedge y)=xy$. If the
cancellative semigroup is a group, then we say that the lattice is
fully starrable. In this paper, it is proved that distributivity
is a strict generalization of starrability. We also show that a
lattice $(X,\le)$ is distributive if and only if there is an
abelian group $(G,+)$ and an injection $f:X\to G$ such that
$f(x)+f(y)=f(x\vee y)+f(x\wedge y)$ for all $x,y\in X$, while it
is fully starrable if and only if there is an abelian group
$(G,+)$ and a bijection $f:X\to G$ such that $f(x)+f(y)=f(x\vee
y)+f(x\wedge y)$, for all $x,y\in X$.
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