to cross one another, typically passing alternately over and under, as if woven together; intertwine

Their hands interlaced.

to unite or arrange (threads, strips, parts, branches, etc.) so as to intercross one another, passing alternately over and under; intertwine.

to mingle; blend.

to diversify, as with threads woven in.

to intersperse; intermingle

She interlaced her lecture on Schubert with some of his songs.