To become old/ turn grey
The hair on his head turned gray. Gray hair was green in his hair. In the question: He grew a beard.
("He who has broken the covenant with his son-in-law and untied his leg, she will sit until her head is covered with thorns" - as written in the 1st chapter of the book of the Law of Moses, and so: "The greatness of Tel Aviv is surrounded by butterflies/ Everything in it is prepared and tested./ We have built in it like a millstone, the shekels are forgotten/ And the shekels are covered with thorns, their heads are like dust" - Yitzhak Yitzhak/ The Garden of Shekels)
Translation
Expression (Hebrew)
הִלְבִּין רֹאשׁוֹ
Definition (Hebrew)
שְׂעַר רֹאשׁוֹ הָפַךְ לְשִׁיבָה. שֵׂיבָה זָרְקָה בִּשְׂעָרוֹ. בְּהַשְׁאָלָה: הִזְדַּקֵּן.
("הַפּוֹסֵק מָעוֹת לַחֲתָנוֹ וּפָשַׁט לוֹ אֶת הָרֶגֶל, תֵּשֵׁב עַד שֶׁתַּלְבִּין רֹאשָׁהּ"- כְּתֻבּוֹת קָט ע"א, וְכֵן:"גִּדְּלָה תֵּל אָבִיב מִסְּבִיבָהּ פַּרְפָּרִים/ הַכֹּל בָּהּ תֻּכְנַן וְנִבְדַּק./ נִבְנוּ בָּהּ כְּבִישִׁים, נִשְׁכְּחוּ הַשִּׁקְמִים/ וְהַלְּבֵין אָז רֹאשָׁם מַאֲבָק"- יִצְחָק יִצְחָקִי/ גַּן הַשִּׁקְמִים)