Bloomsbury Publishing 
Easier English Basic Dictionary [PDF ebook] 
Pre-Intermediate Level. Over 11, 000 Terms Clearly Defined

The Easier English Basic Dictionary’ is designed especially for elementary and pre-intermediate students of English. It includes the basic vocabulary needed to understand and study written and spoken English at this level, and is particularly useful for students taking the Preliminary English Test (PET) or the Key English Test (KET) exams. Clear notes on grammar, irregular verbs and easily confused words, as well as pronunciations for all entries make this a valuable aid to students of English.’