Information available to a player that he is ethically bound to ignore. For example, an inference drawn from a hesitation by partner is ‘unauthorised information’, although, of course, it is legal to act upon an inference drawn from a hesitation by an opponent.
In the first sequence, whatever the partnership agreement, if West does not actually hold both majors, he has a duty to ignore East’s explanation.
In the second sequence, the slow pass suggests that East was thinking of bidding 4♥. West should bid 4♥ only if it is a clear-cut action (unlikely in this particular example).