it where you purposely lose to manipulate your rating down to win against easier opponents. This is a major case in the player leagues where you can gain trophies if you win in a live game
Sandbagging

Basically saying that I am a 1700 strength player but I intentionally lower or disguise myself as a 1000 I can be said to be a sandbagger

when you decrease our rating on purpose to become low elo and then throw bags of sand at low elo players when you win against them

My peak rating in bullet is 2509, but now I am tanking to 2377. If someone intentionally did this, this is sandbagging.

https://support.chess.com/en/articles/8583380-what-is-a-sandbagger
Sandbagging
The term 'Sandbagging' is used when a player intentionally lowers their chess rating by losing games on purpose. This is often done with the intent to enter tournaments at a lower rating level, where they can easily dominate and win prizes.
Sandbagging falls under the broader category of rating manipulation, which includes activities such as:
Arranging game results intentionally.
Playing with multiple accounts.
Choosing the wrong skill level on a new account.
Losing intentionally to lower one's rating.
How to spot a Sandbagger
If you notice a player performing exceptionally well in a tournament, significantly above their stated rating, it might be worth investigating further.
You can review the player’s recent games to see if there are any suspicious patterns:
Sandbaggers often resign multiple games in a row after just a few moves to drop their rating significantly. Some might give away their queen before resigning to disguise it as a blunder or misclick.
If a player has a series of losses right before entering a tournament or club match, it could indicate sandbagging.

I think another example is to have someone else make a new account, get high rated, and then play you and lose on purpose so you can gain rating. There is often a bribing situation to get the other guy to agree.

its where you and a bag of sand get involved with one another and start a relationship
Bruh ;-;

its where you and a bag of sand get involved with one another and start a relationship
Bruh ;-;
Bruh

its where you and a bag of sand get involved with one another and start a relationship
Bruh ;-;
Bruh
Bruh ;-;
Please someone explain sandbagging to me in clear terms someone accused me of sandbagging and I want to know whether he's right or not.