  The set of Schr\"oder words (Schr\"oder language) is endowed with a natural
partial order, which can be conveniently described by interpreting Schr\"oder
words as lattice paths. The resulting poset is called the Schr\"oder pattern
poset. We find closed formulas for the number of Schr\"oder words
covering/covered by a given Schr\"oder word in terms of classical parameters of
the associated Schr\"oder path. We also enumerate several classes of Schr\"oder
avoiding words (with respect to the length), i.e. sets of Schr\"oder words
which do not contain a given Schr\"oder word.

Combinatorics;Discrete Mathematics;Formal Languages and Automata Theory