What does “that sticks” mean in the following line?
What is the most resilient parasite? Bacteria? A virus? An intestinal worm? An idea. Resilient. . . highly contagious. Once an idea has taken hold of the brain it's almost impossible to eradicate. An idea that is fully formed, fully understood. . . that sticks right in there somewhere.
Source: IMDB, Quotes for Dominic Cobb (Character) from Inception (2010)