The antonyms for the phrase 'leave trace' can vary according to the context of its usage. In some instances, antonyms could simply be the opposite of the action i.e. 'erase', 'remove', or 'eliminate' traces. On the other hand, antonyms could be words that indicate that no traces were left behind, such as 'disappear', 'vanish', or 'evaporate'. Words such as 'detected,' 'marked,' and 'noted' could also be considered as antonyms since they indicate that traces have been left behind. In essence, the antonyms for the phrase 'leave trace' are dependent on the situation and can range from the absence of traces to the complete elimination of all existing traces.