Русско-англо-русский юридический словарь

The appellant in the new case can be either the plaintiff (or claimant), defendant, third-party intervenor, or respondent (appellee) from thelower case, depending on who was the losing party. The winning party from the lower court, however, is now the respondent. (Wikipedia)

As a general rule, the losing party pays the costs of the winning party, but the court can order otherwise. (Wikipedia)

However, in countries that abide by English common law, the rule says the losing party must pay the legal fees of the winning party. (Investopedia)