What was the term in the Gilded Age for a new emasculated condition that marked by depression, indigestion, hypochondria, and extreme nervousness?

Neurasthenia

Explanation:

The gilded age refers to the last decades of the nineteenth century that is between the 1870s to about 1900.

The medical term which was used during the Gilded age to refer to the condition caused by the weakness of the nerves or nervous breakdown or nervous illness is Neurasthenia.

The Neurasthenia was marked by the symptoms of the depression, the fight or flight responses such as indigestion, the nervousness and the irritability.

Thus, Neurasthenia is the correct answer.