v.
 combine or be combined to form a single entity. 
▸blend or cause to blend gradually into something else.
 ▸
(usu. merge something in)
 Law  absorb (a title or estate) in another.
Etymology
  C17 (in the sense ‘immerse oneself’): from L. mergere ‘to dip, plunge’; the legal sense is from Anglo-Norman Fr. merger.