To dull the senses of (a person, place etc.).
To make into a narcotic.
To use a narcotic in order to make (someone) drowsy or insensible; to anesthetize, to drug.
To make (something) less innocent or natural; to artificialize.
To make (something) more sophisticated (“complex, developed, or refined”); to develop, to refine.
To make (oneself or someone) more sophisticated (“experienced in the ways of the world, that is, cosmopolitan or worldly-wise”); to cosmopolitanize.
To alter and make impure (something) by mixing it with some foreign or inferior substance, especially with an intention to deceive; to adulterate; (generally) to corrupt or deceive (someone, their thinking, etc.).
To change the meaning of (something) in a deceptive or misleading way.
To practise sophistry (“the (deliberate) making of arguments that seem plausible but are fallacious or misleading”).
A person who is sophisticated (“experienced in the ways of the world, that is, cosmopolitan or worldly-wise”), or who has sophisticated tastes.
Of a person: experienced in the ways of the world; cosmopolitan, worldly-wise.
Of art or other things: appealing to the tastes of an intellectual or sophisticated (sense 1.1) person; cerebral; also, cultured, elegant, refined.