A hypothetical form of a word or part of a word from which attested words have been derived; a form reconstructed in a proto-language.
Early 20th century; earliest use found in Journal African Society. From proto- + form.
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。