In English we’d say that the boule is kissing the jack. What would a French petanque player say?
The French expression is faire un biberon (to make a baby-bottle) or faire un têtard (to make a tadpole). The French seems to suggest that the boule isn’t merely close to the jack, or touching it. The boule is stuck to the jack. Like a baby sucking on a baby-bottle?
Anyway, if you have a question about French petanque terminology, here is one online resource.
All About Petanque 