An automaton (plural: automata or automatons) is a machine capable of self-operating.
Automata within the Dusk Series
Automata within the Dusk Series are "mechanical dolls" created with advanced alchemy from long ago. In order to manufacture an automaton, rare materials and minerials, such as extraordinary valuable prime field crystals were necessary, and thus were not massproduced.
According to Logy, all automata being researched in The Center are out of order.
They have emotions which are similar to humans. Even if sleep or food isn't necessary for them, they can eat. It appears like being able to show many facial expressions is unusual for automata, however, it seems like automata can learn human-like expressions from humans. According to Clone, automata can make small changes to the storage and duplication of information, but cannot create new creations. She also tells that helping humans with starting new things, are what makes them the most happy.