The bird has flown
By metaphor: disappeared. Gone missing.
("And he returned to his brother and said, The child is not here, and I am here; I am coming" - initially to this (Reuven later, who discovered that Joseph had been sold by his brother), and then: "The table is set, and there is wine, and everything is prepared and ready for the feast, but the child is not here" - Agnon/ These and These, From Heaven, 138)
Translation
Expression (Hebrew)
וְהַיֶּלֶד אֵינֶנּוּ
Definition (Hebrew)
בְּהַשְׁאָלָה: נֶעְלָם. הָלַךְ לְאִבּוּד.
("וַיָּשָׁב אֶל אֶחָיו וַיֹּאמַר הַיֶּלֶד אֵינֶנּוּ וַאֲנִי אָנָה אֲנִי בָא"- בְּרֵאשִׁית לז ל (רְאוּבֵן לְאַחַר שֶׁגִּלָּה שֶׁיּוֹסֵף נִמְכַּר ע"י אָחִיו), וְכֵן:"עָרוּךְ הַשֻּׁלְחָן חַלּוֹת וְיַיִן ,הַכֹּל מוּכָן וְעוֹמֵד לִסְעוּדָה, אֲבָל הַיֶּלֶד אֵינֶנּוּ"-עַגְנוֹן/ אֵלּוּ וָאֵלּוּ, מִן הַשָּׁמַיִם, 138)