Rugby Union Positions

Back row - The third line of the scrum, comprising one number 8 and two breakaways (6 & 7). These players are known as the back-rowers.
Back three - The fullback and the two wingers.
Backline - The players who wear jersey numbers 9,10,11,12,13,14 and 15. These players spread out in positions behind the scrum and are not involved in the lineouts. Also known as 'backs'.
Blindside flanker - This is the flanker who binds onto the scrum on the blindside or the short side.
Breakaways - The two forwards in the team who wear the jerseys number 6 and 7 at the start of the game. Replacements will have different numbers. They are also known as flankers and bind on the side of the scrum, with their prime pursuit being to win the ball at the rucks and mauls. They are also important linking men between the other forwards and the backs.
Centre/s - The player wearing the number 12 jersey is known as the 'inside centre' and the player wearing the number 13 jersey is known as the 'outside centre'. They are the heart of a team's attack. The 'inside centre' is sometimes called the 'second five eighth'. When this is the case the number 13 is known as the 'centre'.
Coach - The person in charge of a football team. The 'Boss'.

Learn Play Rugby

Some more Rugby Playing Terms:
Conversion - When a try is scored, the team that scored the try is allowed a free shot at the goal. If successful, two points are added to their score.
Counter Attack - The attacking move in response to an opposition attack, where the ball has passes from one team to another.
Cross Kick - This is the term for a kick across the ground aimed towards the attacking team's openside winger, who plans to run through the defence and re-gather the ball.
Cut- Out Pass - A pass that deliberately misses one or more players then goes to the next player in the attacking line.
Dead - The ball is said to be 'dead' when it is out of play. This occurs when the ball has gone outside the playing area and remained there, or when the referee has blown the whistle to indicate a stoppage, or when a conversion kick is being taken.
Decoy - A player who makes out that he is about to receive the ball in an attempt to deceive the opposition's defensive line. You will hear the person referred to as a 'decoy runner'.
Defence - Used by one team to stop the other team when it is attacking.