The word “manna” means “what is it”? The Israelites did not know what it was. The Bible says it was “a fine, flaky substance, as fine as frost on the ground” (NRSV, Exodus 16:14) and “like coriander seed, white and the taste of it was like wafers made with honey.” (Exodus 16:31) Some scholars theorize that manna was the secretion left by certain insects feeding on tamarisk trees.