Question

What do you mean by steric hindrance??

Answer 1

Steric effects arise from a fact that each atom within a molecule occupies a certain amount of space. If atoms are brought too close together, there is an associated cost in energy due to overlapping electron clouds (Pauli or Born repulsion), and this may affect the molecule's preferred shape (conformation) and reactivity.Steric hindrance occurs when the large size of groups within a molecule  prevents chemical reactions that are observed in related molecules with  smaller groups.

Answer 2

if any bulky group is attached to the central carbon atom then there is sterik inderence