soi-disant vs synthetic

Self-styled; self-proclaimed. 

Artificial, not genuine. 

Of, or relating to synthesis. 

Produced by synthesis instead of being isolated from a natural source (but may be identical to a product so obtained). 

Produced by synthesis, thought to have the same effect as its natural counterpart, but chemically different from it. 

Pertaining to the joining of bound morphemes in a word (compare analytic). 

Of a language, having a grammar principally dependent on the use of bound morphemes to indicate syntactic relationships (compare analytic).