What is the meaning of Weick's sensemaking theory?

Very simply, Weick's sensemaking theory examines the cognitive processes that underlie the ways people make sense of ambiguous situations. Essentially, the theory asks, "how does somebody try to make sense of a situation?". 
According to Weick's original theory, sensemaking has 7 different properties: 
1. Identity: People's understanding of who they are influences how they make sense of things
2. Retrospect: People tend to make sense of things after the fact; that is, they put the pieces together in a meaningful way after the event or situation has occurred. 
3. Socialization: Somebody's life experience, including childhood experiences and social context, will determine how they make sense of situations. 
4. Enaction: People will enact new situations through stories (narratives) and conversations with others (dialogue). Shared stories help people understand and organize their own experiences. 
5. Ongoing nature: Sensemaking has an ongoing nature, because people will consider and reconsider situations over time, whilst simultaneously reacting to new situations. We are constantly trying to make sense of something. 
6. Extracted cues: People take cues from the context of the situation (i.e. the people and environment involved) and try to use that information to guide their interpretation of a situation. 
7. Plausibility: People will bring together all of the above elements and attempt to develop a plausible way to make sense of a situation, by taking into account their prior knowledge, situational cues, and context.