Rainbow Six Siege Wiki
Rainbow Six Siege has one vocabulary for the round itself and another for everything around it: weapon attachments, cosmetics and chat. The Onlyfarms wiki covers both, with every term listed A-Z below.
Bomb is the mode where attackers have to locate and defuse one of two bombs, or eliminate the defenders, while the defenders try to stop them by killing every attacker or destroying the defuser. On the loadout side, Angled Grip is the grip that speeds up reloads, next to the Vertical Grip for recoil control and the Horizontal Grip for movement speed. Burst Fire and Anchor are listed too. More terms get pages of their own: Text Chat, Badge and Banner, plus the Victory Pose, an animation that comes with an operator's Elite set.
Onlyfarms has Rainbow Six Siege services next to the wiki. Words that many games share, rather than Siege alone, are explained in the general gaming wiki.