/up"euhr mohst'/ or, esp. Brit., /-meuhst/ , adj. Also, upmost .
1. highest in place, order, rank, power, etc.: the uppermost peaks of the mountain; the uppermost class of society.
2. topmost; predominant: a subject of uppermost concern.
adv.
3. in or into the uppermost place, rank, or predominance: The blossoms grow uppermost on the stems of these flowers; the thoughts that came uppermost to her mind.
[ 1475-85; UPPER 1 + -MOST ]