What is a piece of broken pottery or fragment of glass called?

A piece of broken pottery or a fragment of glass is referred to as a shard. The term "shard" specifically describes these small, often sharp pieces that result from the breaking of ceramic materials or glass. Shards can be significant in various fields, such as archaeology and art history, as they can provide insights into past human activity, manufacturing techniques, and even historical contexts.

In contrast, the other terms listed do not relate to pieces of broken materials. A shovel is a tool used for digging, lifting, and moving bulk materials; squalid refers to a state of being extremely dirty and unpleasant, often linked to poverty or neglect; and scorch describes the act of burning something slightly or causing it to become discolored through heat. Each of these terms serves a different purpose and context, which highlights the specificity and relevance of "shard" when discussing broken pottery or glass.