What is the meaning of the word "pseudo"?

Definitions:

A pretentious or insincere person. NOUN
- The pseudo philosopher attempted to pass off his shallow ideas as profound wisdom.
Comes from the Greek word pseudes, meaning false or deceptive. ADJECTIVE
- His pseudo-intellectual demeanor fooled many into believing he was well-read.
Used to form words that indicate something that resembles or imitates something else but is not genuine or true. PREFIX
- She wore a pseudo diamond necklace that looked real from a distance.