(as it is used in this verse) means,

Way of life; conduct;
behavior; deportment;
especially with respect
to morals.
And you hath He quickened
who were dead in trespasses and sins;
Wherein in time past ye walked
according to the course of this world,
according to the prince of the power of the air,
the spirit that now worketh
in the children of disobedience:
Among whom also we all had our conversation
in times past in the lusts of our flesh,
fulfilling the desires of the flesh
and of the mind; and were by nature
the children of wrath,
even as others.