I can’t bear this sort of talk but these are the phrases and definitions I’ve learned since joining the forum:
to bash - to go back and forth on trains for no purpose other than to ride them, not to make a journey
to bail - to make a random decision to alight a train, without it having been planned to do so
winner - a train that an enthusiast has not travelled on before, or one they have not seen before
dud - antonym of winner, see above
stalker - the one train that an enthusiast constantly sees, e.g. 444013 always seems to turn up when I take SWR from Woking
loophole - a mistake or error in the ticketing restrictions or booking websites that allow one to conveniently make a journey for a much cheaper price or along a more complex route than is technically valid - but according to the conditions of travel, tickets bought using a loophole are legal for you to use
to score - to travel on a winner, see above
to be gripped - to have your ticket marked, stamped or scribbled on by railway personnel so that it cannot be sneakily reused
to clear - to have been on, or to have seen, (depending on whether you record sightings or haulages) all trains within a class, e.g. clearing 450s would be to travel on all 127 of them
to flag - to purposely miss a train, e.g. a spotter might flag a unit he has already been on (a dud) so that he can catch the next train which he might not have been on (a winner)