adhesion

Short definition from Wiktionary

Noun

1. 1
   The ability of a substance to stick to an unlike substance.
2. 2
   Persistent attachment or loyalty.
3. 3
   An agreement to adhere.
4. 4
   An abnormal union of surface by the formation of new tissue resulting from an inflammatory process.
5. 5
   The binding of a cell to a surface or substrate.
6. 6
   The frictional grip on a surface, of wheels, shoes etc.