1. Plural of plastrum; the ventral (belly) part of a turtle's or tortoise's shell.
Usage: zoology; comparative anatomy
2. Plural of plastrum; a protective breastplate or chest piece worn in fencing or martial arts.
Usage: sports; historical

Examples

• The scientist examined the plastrums of several turtle specimens to study their growth patterns.
• Fencers wear padded plastrums to protect their chests during competition.
• The tortoise's plastrums were marked with distinctive growth rings.
• Different species of turtles have plastrums with varying shapes and textures.
• The museum displayed ancient plastrums alongside other pieces of armor.