Antonyms for the phrase "are contiguous to" would be words that signify distance or separation. Examples of such words include apart, distant, detached, disconnected, disjoined, isolated, and remote. "Apart" indicates that two things are at a distance from each other, while "distant" carries a similar meaning but also emphasizes that the distance is great. "Disconnected" and "disjoined" imply a lack of connection or relationship between the two things, while "isolated" suggests that one of the things is alone and separate from others. "Remote" indicates that something is far away from another thing, either in physical or emotional proximity.