In QFS discourse, colinearity means going in the same direction. Colinear people have a natural tendency to head in the same direction. Colinearity does not imply sameness of experience or equal level of knowledge or advancement but it does imply seeking in the same fundamental direction. The word is most often used in the context of aspiring to be of service to others.
As people work in a collinear direction, they acquire similar experiences and understandings. In general, esoteric work strives to increase one's objectivity. Thus the world and its effects, as well as the workings of the self appear increasingly in a common light to people following collinear paths.
As people near the esoteric circle of humanity, they reach a point where one can no longer both understand and disagree. This is a natural effect born of seeing the world as it is and has nothing to do with compulsion or any imposed set of beliefs.
Thus colinearity with the Work or QFS starts with usually a vague questing for something higher and develops into personally verified experiential knowledge.
Colinearity is not a fixed given. People may start with the idea of their colinearity with the Work but experience may demonstrate that they in fact seek something else. Even in such a case, the seeker has made definite constatations on the self.
Colinearity is tied with the concept of immutable nature or 'consciousness director.' This inner nature predisposes one for expressing service to others or service to self. People with different consciousness directors may study together but they will interpret what they find differently. Knowing the same information does not thus make colinearity, nor does any regime or schedule of work make colinearity. Preexisting colinearity can however manifest through knowing the same information and/or working together.
Synergy is more likely to occur in a colinear group than in a non-colinear one, we could say that synergy is not the same thing as colinearity but may be its result.
Colinearity at an advanced level may lead to people forming a group in the esoteric sense, as is alluded to in the New Testament when speaking of the congregation being the body of Christ. What is gained or lost by one is gained and lost by all and where the head goes there follows the body. Also, such a group may hold more of the "stuff of knowledge" or "being" than the individuals composing it separately, thus it may be "wiser" or more "intelligent" than its constituents. We note that the esoterically colinear group is a rare special case, since ordinary groups tend to condense around the lowest common denominator.