Tawdry means "cheap and gaudy in appearance." Its story begins with a 7th-century queen who renounced her royal life and became a saintly abbess.
Suffering from a fatal condition that included a swelling in her throat, the dying abbess attributed that symptom to God's punishment for her onetime fondness for necklaces.
After her death, the abbess became Saint Audrey, and her shrine became a popular site for English pilgrims. At an annual fair in her honor, all sorts of cheap knickknacks and jewelry were sold, including a type of necklace called Saint Audrey's lace.
By the 17th century, St. Audrey's lace had become tawdry lace. Tawdry came to be applied to other cheap goods sold at these fairs and from there to other tastelessly showy things.