The term 'wingless bloodsucker' can be summarized by two crossword solutions: FLEA (4 letters) and BEDBUG (6 letters). Fleas are small, wingless insects that feed on the blood of mammals and birds. They are usually found in carpets, furniture, and pet fur. Bedbugs are also wingless insects that feed on the blood of humans and animals. They are typically found in mattresses, bedding, and furniture. Both fleas and bedbugs are considered pests due to their ability to spread disease and cause discomfort.