I recently saw this word used in a Android SE post and at first I thought the user misspelt the word but actually I found that a word "phantastic" exists.
The phantastic meaning of yourdictionary website tells its the dated version of the word fantastic.
phantastic - Adjective (comparative more phantastic, superlative most phantastic)
I couldn't properly understand when we should actually use the word. Can someone show some examples of the usage of the word. What does a dated form of a word mean?