The phrase "resistless tendency" refers to a force or direction that is difficult or impossible to resist. Synonyms for this phrase could include irresistible impulse, overwhelming inclination, inexorable pull, or unstoppable compulsion. Some other words that could be used to convey a similar meaning include inexorable, relentless, compelling, or overpowering. These words all describe a force that is difficult to resist or stop, and may be used in a variety of contexts, from describing a physical force like gravity, to describing a psychological or emotional drive. Understanding synonyms for common phrases like "resistless tendency" can help writers express themselves more clearly and precisely.