General Definition:
1. Any thing which is long and thin with a small sphere-like protrusion at one end, or any thing or any action that is directly or indirectly associated with this, such as a knob or berry, or the action of chalking a snooker cue.
As a Noun:
1. A rounded lump on the end of a stick or post. English = knob.
2. A small piece of rock. English = stone.
3. A kind of small, round fruit that grows on a bush or tree, some of which you can eat. English = berry.
4. A small piece of coloured glass, wood, or plastic with a hole through the middle. English = bead.
As a Verb or Adjective:
1. To use a piece of chalk to dust the end of a snooker cue, to chalk the cue.