Cucumber is used mostly literally for salads, pickling, or the idiom 'cool as a cucumber' (calm, unbothered), which makes it a handy shorthand for staying composed under pressure. It arrived in Unicode 9 (2017), later than many staple vegetables, and its long green form with visible seed-flecked cross-sections in some renderings keeps it visually simple.
Keywords: cucumber, food, pickle, vegetable