Strong's #534: 'amiyr (pronounced aw-meer')
 apparently from 559 (in the sense of self- exaltation); a summit (of a tree or mountain:--bough, branch.
Brown-Driver-Briggs Hebrew Lexicon:
 
  'âmı̂yr 
 
 1) top, summit
 
 1a) of tree
 1b) of mountain
 
  Part of Speech: noun masculine
Relation: apparently from H559 (sense of self-exaltation)
Usage:
This word is used 2 times:
Isaiah 17:6: "or three berries in the top  of the uppermost bough, four or five in the outermost fruitful branches"
Isaiah 17:9: "be as a forsaken bough,  and an uppermost branch, they left because"