One key to understanding apocalyptic scripture is to follow the pattern in Daniel and Revelation:

1) Revelation, dream, or vision using symbolic imagery occurs

2) That symbolism is explained in straight forward literal terms (often by an angel)

Harlot - pŏrnē - Prostitute - Sells itself or its resources (what they have) for money

Fornication - pŏrnĕuō - To act the harlot

Wilderness - ĕrēmŏs - Lonely, deserted, solitary place; desert

Blasphemy - blasphēmia - Insult, defamation, slander or disrespect for God

Mother of - Figure of speech that means major or best