periodical [,piəri'ɔdikəl]n.a publication that appears at fixed intervalsa periodical dedicated to a particular subjecteg. he reads the medical journals, She discussed these problems in detail in an article in the Indian Journal of MedicalMicrobiology in 2008. 另外journal还可以指日记，日志， 日报等，Eg. the Wall Street Journal, 华尔街日报。
