The word "trapa" refers to a small group of plants, specifically a type of water plant that is known for its edible seeds. These plants are often found in water and are part of the family of aquatic herbs. One common name for these plants is "water chestnut."
In more advanced discussions, you might find "trapa" used in botany or ecology when describing aquatic ecosystems or in culinary contexts when discussing ingredients in Asian cuisine.
There are no common idioms or phrasal verbs specifically associated with "trapa," as it is mainly a scientific term.
"Trapa" is a noun that refers to a genus of aquatic plants known for their edible seeds, commonly called water chestnuts.