They said one to another, this is manna. Rather, "this is a gift." To suppose that they recognised the substance as one known to them in Egypt under the name of menu or mennu, is to make this clause contradict the next.
To translate "what is this?" gives good sense, but is against grammar, since the Hebrew for "what" is not man but mah. The Septuagint translators (who render τί ἐστι τοῦτο) were probably deceived by their familiarity with the Chaldee, in which man corresponds to "what."
Not knowing what to call the substance, the Israelites said one to another, "it is a gift"—meaning a gift from heaven, God's gift (compare Exodus 16:8); and afterwards, in consequence of this, the word man (properly "gift") became the accepted name of the thing.