Here are some possibilities:
* "Sup": This is a shortened version of "What's up?" It's a common greeting, often used in casual conversations.
* "Sope": This is a Mexican dish made of masa dough, often fried or grilled.
* "Soap": This word could be used slangily to mean "to lie" or "to gossip," but it's not very common.
Can you provide more context? For example, where did you hear the word "soup" used in a slangy way? This would help me figure out what you meant.