Synonyms for Informed (same or very similar meaning)
WordNet sense 1 (alert and fully informed):
knowledgeable
WordNet sense 2 (having or based on relevant experience):
enlightened
WordNet sense 3 ((usually followed by `with') well informed about or knowing thoroughly):
familiar
WordNet sense 4 (being up to particular standard or level especially in being up to date in knowledge):
abreast, au courant
From the ODE community, based on WordNet
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