procnemial
/ˌprɒsɪˈnɛmiəl/Definitions
1. adjective
of or relating to a preliminary or introductory movement, step, or action
“The procnemial dance of the ritual was a series of intricate steps performed by the lead dancer.”
2. noun
a preliminary or introductory movement, step, or action, especially one that sets the tone for what follows
“The procnemial phrase of the poem was a powerful metaphor that set the tone for the rest of the work.”