bps = blocks per second. This is used to measure both flight speed and scaffold speed.
flag/flagging = the anticheat detecting you and performing a lagback of some sorts, something like hypixel's lagbacks if you hop too hard.
hopper = A bhopper, particularly in hypixel pit
kcals/sniping group = An organized group of cheaters who 'snipe' winstreaks on bedwars for money.
bypass = a means of evading the anticheat of a server. certain clients may be defined as "bypassing (servername)" this means that 95% of the time you won't be detected by the anticheat on that server if you know what you're doing.
newfag = a new anarchy player.
script = an "addon" or "extension" of sorts for cheats. These can go anywhere from warning you if someone drinks a strength potion to outright clicktp
infaura/tpaura = a form of killaura which spoofs you to teleport to and away from players rapidly as you hit, giving you enormous amounts of reach.