Definitions:

1. To cause problems that make it hard for something to happen or continue. VERB
   • Budget cuts have stymied the school's efforts to expand its programs.
2. To obstruct or impede the progress or success of something. VERB
   • The sudden change in regulations stymied the project's development.

Synonyms:

• block
• frustrate
• hamper
• hinder
• impede
• obstruct
• thwart