The dance of legislation has more steps and rules (and foot and toe stomping opportunities) than a few words defined, but learning the Language of Congress is a good place to start:
“Sessions, Adjournments, and Recesses of Congress,“ by Richard S. Beth, Specialist on Congress and the Legislative Process, and Jessica Tollestrup, Analyst on Congress and the Legislative Process, February 27, 2013:
“The House and Senate use the terms session, adjournment, and recess in both informal and more formal ways, but the concepts apply in parallel ways to both the daily and the annual activities of Congress. A session begins when the chamber convenes and ends when it adjourns. A recess, by contrast, does not terminate a session, but only suspends it temporarily…. [Link to full CRS Report
A regular annual session of Congress begins when the two chambers convene in January, pursuant to the Constitution (or to law). An annual session ends with an adjournment sine die. Until the next annual session convenes, Congress is then in a period of sine die adjournment (or “intersession recess”). If the President were to call an additional, “extraordinary” session, it would be procedurally similar to a regular annual session. …” [Link to full CRS report.]