Why are elimination reactions in organic chemistry known as beta eliminations? Why are organic elimination reactions known as beta eliminations? Why don't we call them alpha eliminations?
In an elimination reaction we typically have a leaving group (denoted by "X" in the figure below),  The carbon that the leaving group is attached to is referred to as the "alpha" carbon.  If a hydrogen is removed from the "beta" carbon, then we have formed an olefin and the reaction is called a beta elimination.



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Sometimes an alpha hydrogen can be removed.  In this case both the hydrogen and leaving group were attached to the same carbon and a carbene is formed.