(An exception to this rule is the Super League, which uses static squad numbering.) In rugby union:
One of the two starting locks wears the jersey number 4. In the standard bonus points system, a point is awarded in the league standings to a team that scores at least 4 tries in a match, regardless of the match result. In other fields
The phrase "four-letter word" is used to describe many swear words in the English language. Four is the only number whose name in English has the same number of letters as its value. Four (四, formal writing: 肆, pinyin sì) is considered an unlucky number in Chinese, Korean, Vietnamese and Japanese cultures mostly in Eastern Asia because it sounds like the word "death" (死, pinyin sǐ). To avoid complaints from people with tetraphobia, many numbered product lines skip the "four": e.g. Nokia cell phones (there was no series beginning with a 4 until the Nokia 4.2), Palm PDAs, etc. Some buildings skip floor 4 or replace the number with the letter "F", particularly in heavily Asian areas. See tetraphobia and Numbers in Chinese culture. In Pythagorean numerology (a pseudocience) the number 4 represents security and stability. The number of characters in a canonical four-character idiom. In the NATO phonetic alphabet, the digit 4 is called "fower". In astrology, Cancer is the 4th astrological sign of the Zodiac. In Tarot, The Emperor is the fourth trump or Major Arcana card.
Five-dimensional and every higher dimension: zero regular star-polytopes; uniform star polytopes in dimensions 
  
    
      
        n
      
    
    {\displaystyle n}
   > 
  
    
      
        4
      
    
    {\displaystyle 4}
   are the most symmetric, which mainly originate from stellations of regular 
  
    
      
        n
      
    
    {\displaystyle n}
  -polytopes.Altogether, sixteen (or 16 = 42) regular convex and star polychora are generated from symmetries of four (4) Coxeter Weyl groups and point groups in the fourth dimension: the 
  
    
      
        
          
            A
          
          
            4
          
        
      
    
    {\displaystyle \mathrm {A} _{4}}
   simplex, 
  
    
      
        
          
            B
          
          
            4
          
        
      
    
    {\displaystyle \mathrm {B} _{4}}
   hypercube, 
  
    
      
        
          
            F
          
          
            4
          
        
      
    
    {\displaystyle \mathrm {F} _{4}}
   icositetrachoric, and 
  
    
      
        
          
            H
          
          
            4
          
        
      
    
    {\displaystyle \mathrm {H} _{4}}
   hexacosichoric groups; with the 
  
    
      
        
          
            D
          
          
            4
          
        
      
    
    {\displaystyle \mathrm {D} _{4}}
   demihypercube group generating two alternative constructions.