The most common and most likely answer to this crossword clue is the 5 letter word CLASS
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Buddy explains!
The straight part
We know that "Outstanding/lesson" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case outstanding/lesson = class.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CLASS mean?
CLASS noun- A group, collection, category or set sharing characteristics or attributes.
- A social grouping, based on job, wealth, etc. In Britain, society is commonly split into three main classes; upper class, middle class and working class.
- The division of society into classes.
- Admirable behavior; elegance.
- A group of students in a regularly scheduled meeting with a teacher.
- A series of lessons covering a single subject.
- A group of students who commenced or completed their education during a particular year. A school class.
- A category of seats in an airplane, train or other means of mass transportation.
- A rank in the classification of organisms, below phylum and above order; a taxon of that rank.
- Best of its kind.
- A grouping of data values in an interval, often used for computation of a frequency distribution.
- A collection of sets definable by a shared property.
- A group of people subject to be conscripted in the same military draft, or more narrowly those persons actually conscripted in a particular draft.
- A set of objects having the same behavior (but typically differing in state), or a template defining such a set.
- One of the sections into which a Methodist church or congregation is divided, supervised by a class leader.
- To assign to a class; to classify.
- To be grouped or classed.
- To divide into classes, as students; to form into, or place in, a class or classes.
- Great; fabulous