A few days ago I was trying to learn the vernacular so I searched League of Legends Dictionary and got this forum post, nothing official.
League of Legends Glossary/Dictionary/ Abbrevations/Thesaurus - League of Legends Community
League of Legends Glossary/Dictionary/ Abbrevations/Thesaurus - League of Legends Community
Carry - The meaning of carry varies from player to player, and so it?s hard to pinpoint one exact definition that will encompass all meanings. A carry is a champion who is very weak early game and so needs to be ?carried? by his team in order to survive. But is extremely strong late game and then does most of the continuous damage of the team and so can ?carry? the team. These champions are usually champions that rely on autoattacks for their main damage output (in which case they are called AD carries - because the items they buy focus on their Attack Damage) , and autoattacks only really start to do a lot of damage when you have a lot of items to support them, hence why you?ll only be strong late game, when you have all your items. Carries often go in the bottom lane together with a support champion who supports/helps/carries them during their difficult early laning phase. Even during mid and late game, though they have a high damage output, they will still be very squishy and so will need a tank or other champions to protect or ?carry? them.
Some champions are sometimes referred to as AP carries, these would be champions that are able to put out a continuous large amount of magic damage in late game (but usually throughout the game).
Players often say ?I carried this game? or ?I carried this team? and this is not a reference to one of the specific definitions above but just a general way of boasting and saying they were the best on their team and they were the deciding factor in bringing their team to victory.