Near the bumpers at the centre top of the table there is a hidden lane that gives you a letter each time you get the ball through it.
Every successful time you will get a letter spelling W-O-R-D appear in the dot matrix. Each time you get all 4 letters, you add x2 to the multiplier. The achievement opos when you get x10. This means you have to get all 4 letters 5 times, which is 20 times in total.
Edit: It does have to be the same ball, unless you get a multipliers held. Not sure in how you get that though.
Getting this is tricky, you have to hit the ball round the the top orbit so that it gets to just right of the top centre and falls down, but doesn’t have enough power to complete the full orbit. there are two strategies which help.
1. If you trap the ball with the bottom left flipper, then release and hit immediently, you should hit the ball straight up through the flower lane. It will have enough power to get to the top of the lane, round near the bumpers and score a letter. But not enough power that it goes around the orbit.
2. If you hit the ball round the top orbit, then when it reaches the centre you can tilt the opposite way to the direction the ball is travelling. Just be carefull to only tilt once, or you lock the table. This doesn’t work when its travelling really fast, but it will stop a slower ball that would otherwise travel the full orbit.