A more thorough explanation:

yea

Yea means "yes". It is used in oral voting and also written or spoken when announcing vote results.

For example, in John Doe No. 1 v. Reed, the Supreme Court used the word "yea" to indicate a positive vote.

During a vote, the chairperson may ask, "All in favor say yea." If the majority of people say "yea", the motion passes. When the results are announced, the chairperson may say, "The motion passes with 10 yeas and 5 nays."

These examples illustrate how "yea" is used to indicate a positive vote and to announce the results of a vote.

Aye

Nay (contrast)