Mondayish adjective 3adverb 1forms 2 adjective3 •(informal) grumpy and disheartened on returning to work on a Monday after the weekendI feel a bit Mondayish this week at the start of a long project. •(informal) feeling ill, especially used of clergymen having worked all day SundayI wonder if on this Monday morning all the world is rested? No, no! Many of the best people of the world feel Mondayish. They overdid the Sunday and had no rest. — 1798 •(informal) hungover after a weekend of drinking (as a presumed contributing explanation for a clergyman feeling Mondayish) adverb1 •(informal) On or around Monday.I hope to have the job finished by Mondayish. formsmore Mondayish · most Mondayish