These Latin abbreviations are found in many courthouse documents, particularly land records and court cases When time is limited and you are looking through indexes to land or court records, pay close attention to cases where these abbreviations are used.
"Etal" means "and others" indicating that your ancestor and other people are selling property, buying property, suing someone, or being sued. "Etux" means "and spouse" and that your ancestor and their spouse are selling, buying, suing, or being sued. Whenever a group of people are involved in a court case or a land record, it has higher potential to provide genealogically relevant information.
Particularly when it is Friday at 3:30 and the courthouse closes at 4:00!