Terminology used by players.

Blocker

A blocker is a player who intentionally fails or kills other people.

If you see someone blocking you can report him on the discord server in the #reports channel.

Blocker Servers

These are servers based on the DDNet mod where you can block freely.

Follow

Example: "you flw?"

Asks you to follow onto another server.

Fail

This is a common term used by players to refer to the state where you can no longer progress on the map, be it because everyone is frozen, or you can't do a part alone and your partners are not in a place you can reach.

Failing in DDNet is pretty common, especially in harder map difficulties such as DDmaX, Oldschool, Moderate, Brutal and Insane since these maps have faily parts.

Faily part

We refer to this term for map parts where you can fail.

Acronyms

"hh" means hammer hit.

"hf" means hammer fly.
"rf" means rocket fly.
"give hit" can mean to unfreeze using the hammer, or also to throw.
"dj" means double jump.
"sg" means shotgun.
"re" means restart, to start the map from the beginning again.
"flw" means follow.