资料来源 : pyDict

反光信号

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

Heliogram \He"li*o*gram\, n. [Helio- + -gram.]
   A message transmitted by a heliograph.

资料来源 : WordNet®

heliogram
     n : a message transmitted by means of the sun's rays