Without cost, free of charge; involving no loss or sacrifice.
Early 16th century; earliest use found in Alexander Barclay (c1484–1552), poet and clergyman. From cost + -less.
英汉双解词典包含464360条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。