blocker

noun15

1. •
   Agent noun of block (“obstruct or prevent”); something that blocks something else.
2. •
   One who blocks or impedes the movement of an opponent.
3. •
   A defensive or low-scoring batter.
4. •
   One who prevents another user from contacting them electronically.

   • Likewise, any connections shared between your child (the blocker) and the user being blocked will also be broken. — 2013
5. •
   An application or feature that stops or impedes something.
6. •
   A bug or issue that prevents software from being released.
7. •
   A gatekeeper who refuses the marketer access to the person they wish to contact.

   • Sometimes your sales progress skids to a halt. We've all met more blockers than we'd care to. Some are assigned by the company to filter services […] — 1992
8. •
   Any of various medications that block (inhibit) the activity of a chemical messenger or its receptors, such as cardiac conduction modifiers (e.g., alpha-blockers, beta-blockers), gastric acid inhibitors (H₂ histamine blockers), puberty blockers, and others.
9. •
   A close-fitting rectangular glove worn by a goalie in multiple forms of hockey.
10. •
    A playing card, needed by one player, that is held by another.
11. •
    [in compounds] A resident or member of a particular block.

    • For some inexplicable reason, remote controls are allowed only on D block (the drug-free block). Result? D blockers trade their remotes for drugs. Prison logic. — 2003
12. •
    A person who roughly shapes a diamond.
13. •
    A person who blocks (stretches or moulds) or more generally makes knitted items, hats, books (or book covers), shoes, etc.
14. •
    A blocker bet.
15. •
    (slang, no longer used) Synonym of block ornament (“a cheap piece of meat of poor quality”).

    • Forced to substitute a ‘blocker’ of meat, with its cheap accompaniment of bread and vegetables..for poultry and rump-steaks. — 1848