noun

1. the act of sticking (to something) or the state of being stuck together
2. devoted attachment; adherence
3. a thing that adheres
4. Med.
   1. the joining together, by fibrous tissue, of bodily parts or tissues that are normally separate: it typically results from inflammation
   2. a band of fibrous tissue abnormally joining bodily parts or tissues
5. Physics the force that holds together the molecules of unlike substances whose surfaces are in contact

Etymology: Fr < L adhaesio < pp. of adhaerere: see adhere