Returns progress for one saved word. The overall level (new, learning, learned or mastered; inbox when the word has no meanings) comes from its weakest meaning or skill; learned requires every meaning plus writing, listening and speaking to be in regular reviews. Each meaning and each skill has a status (new: not practised yet and never due; learning: in short early steps; due: ready now, staying due for the rest of the learner's day; scheduled: next practice on a later date), a level, review counts and available dates. timezone is an IANA name; when omitted, dates use UTC.