What`s the Grave Key and what does it do?

steve martin wrote on his article at kenstone.net the following

However, there are occasions where you might need to temporarily break the connection during certain types of edit operations. To override the absolute clip connection, hold down the Grave key before moving the clip or performing slip and slide trims.

what is the grave key and what function does he describe (so i can find it in the command panel)?

Key in the upper left of the keyboard shared with the tilde key, the backward apostrophe used as an accent in French.

that key is on my keyboard, when i switch to the u.s. keyboard, right next to the z key and it doesn't do anything in fcpx

update

strange, now it does it :blush:

anyway, the command is "overwrite connection"

i switched back to my german keyboard and had to add this command manually.