They refer to the spoken words, incantations, or phrases that a spellcaster must recite in order to invoke the magical energies necessary to cast a Spell. These verbal components add an immersive and thematic element to spellcasting, requiring players to describe their character's mystical words and gestures as part of the gameplay. The use of verbal components not only enhances the role-playing experience but also introduces a level of strategic decision-making as characters must find opportunities to speak their incantations, potentially risking discovery by enemies or challenges in maintaining concentration during intense situations.
They are typically loud, and can be beard at least up to Near with no check required.
This is ultimately up to GMD if the bender tries to cast a Spell with an enemy nearby, or in an adjacent room or Encounter to determine if an Attention Skill Roll is required.