The name Alejandra is a Spanish feminine form of the masculine name Alejandro, which is derived from the Ancient Greek name Alexandros. The name Alexandros is composed of the elements alexo, meaning "to defend" or "to protect," and aner, meaning "man." Thus, the name Alejandra can be interpreted to mean "defender of man" or "protector of man."

The name Alejandra has its roots in the Hellenistic period, when the Macedonian ruler Alexander the Great conquered vast territories, spreading Greek culture and language across the Mediterranean region and beyond. The name Alejandra gained popularity in the areas influenced by Greek and later Roman civilizations, particularly in the Iberian Peninsula, which was under Roman rule for several centuries.

One of the earliest recorded instances of the name Alejandra can be found in the 12th century, when a Spanish noblewoman named Alejandra de Castilla was mentioned in historical records. Another notable figure bearing this name was Alejandra Pizarro, a 16th-century Spanish conquistadora and the illegitimate daughter of the famous conquistador Francisco Pizarro.

Throughout history, several influential women have borne the name Alejandra. In the 19th century, Alejandra Arango Muñoz (1828-1891) was a prominent Colombian writer and activist who fought for women's rights and education. Another notable Alejandra was Alejandra Soler (1913-2017), a Mexican actress and singer who had a prolific career spanning over seven decades.

In the 20th century, Alejandra Soler (1913-2017), a Mexican actress and singer, enjoyed a remarkable career that spanned over seven decades. Alejandra Guzmán (born 1968), a Mexican singer and actress, has been a prominent figure in the Latin American entertainment industry for several decades.

One of the most famous historical figures with the name Alejandra was Alejandra Feodorovna (1872-1918), the last Empress of Russia. Born Princess Alix of Hesse and by Rhine, she married Tsar Nicholas II and was tragically executed along with her husband and children during the Russian Revolution.