Freedom
In school there were few subjects I really hated, but somehow physics ended up being one of them. Therefore when my husband (who is a railway engineer) starts talking about anything too techy, my brain instantly wants to shut off. The other night, however, we ended up talking about the "degree of freedom" which apparently is a thing in physics ;-) I even looked it up: "In physics, the degrees of freedom (DOF) of a mechanical system is the number of independent parameters that define its configuration or state." (Wikipedia) Please bear with me ;-) So in a nutshell, what I took away from the article is the question: in which directions is a body able to move? (Physicists, don't hate me for this rather naive summary...