Cob/kɑːb/ Definition 1 of 4Pro Tip 1/3Eating Context Used when talking about eating corn in its whole form, directly from the cob. She preferred her corn cooked on the cob. Pro Tip 2/3Versatile Idiom The term can appear in idioms like 'a corncob', which refer to something being particularly difficult. This math problem is a real corncob. Pro Tip 3/3Seasonal Term Often mentioned during harvest season or Thanksgiving in a cultural context. They decorated the table with corn cobs for Thanksgiving.