资料来源 : pyDict

海平面,平均海面

资料来源 : Webster's Revised Unabridged Dictionary (1913)

Sea level \Sea" lev"el\
   The level of the surface of the sea; any surface on the same
   level with the sea.

资料来源 : WordNet®

sea level
     n : level of the ocean's surface (especially that halfway
         between mean high and low tide); used as a standard in
         reckoning land elevation or sea depth