Assalaamu alaykum. My wife and I have a newborn (two months old now), and we named her Tameemah because my wife's mother was named Tameemah, but she died while my wife was a child (may Allah have mercy upon her). Is it haram to give the name Tameemah to a newborn? Can you please explain in as much detail as you can why or why not? May Allah reward you.

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.

There is no religious impediment to naming the newborn after a dead person. Ibn Baaz was asked, "Is it permissible to name the newborn son after his deceased brother, or should we choose another name for him?" He replied, "There is no harm in naming the newborn after his deceased brother."

As for the name Tameemah, there is no harm in giving it to a baby girl; it is the feminine form of Tameem. The Prophet, sallallahu ‘alayhi wa sallam, approved the name Tameem and did not command the Companions bearing it to change it. For instance, there was Tameem Ad-Daari, may Allah be pleased with him, as well as others. This indicates the permissibility of bearing the name Tameem (and accordingly its feminine form Tameemah).

Allah knows best.