Spat has multiple meanings depending on the context. Here are some of the definitions found in the search results:

• Spat (noun): A young bivalve (such as an oyster) . A short gaiter worn over the instep and usually fastened under the foot with a strap, worn especially in the late 19th and early 20th centuries. A brief petty quarrel or angry outburst. A sound like that of rain falling in large drops.

• Spat (verb): Past tense and past participle of spit. To quarrel pettily or briefly. To strike with a sound like that of rain falling in large drops. To engage in a petty quarrel or dispute. To splash or spatter; rain spatting against the window.

• Spat (oyster): When oysters reproduce, they spawn tiny larvae that find an appropriate habitat with a structure to settle on. Once the larvae permanently attach to a surface, they are known as spat.

In summary, spat can refer to a type of shellfish, a short gaiter worn over the instep, a brief petty quarrel or angry outburst, a sound like that of rain falling in large drops, or the past tense and past participle of spit.