  We elaborate on the notion of a filtration of an operad defined in terms of a
lattice-valued operad serving as an indexing object. That covers ordinary
integer-indexed filtrations of associative algebras and operads as a special
case, yet the notion appears to be natural enough to encompass examples of
other kind as well. The characteristic property of lattice operads is that of a
certain distributivity of partial compositions with respect to meets and joins.
We observe that some well-known families of lattices of combinatorial origin,
such as Tamari lattices, assemble to operads subject to this particular
property. Other examples include an operad of integer paritions supported on
Young's lattice, operads of integer compositions of types $A, B$ and $D$, which
we relate to operads of regular polytopes.
