IPA: /oʊˈlɛkrəˌnɒn/
KK: /oʊˈlɛkrənɒn/
The bony part at the back of the elbow that you can feel when you touch your elbow.
He bumped his olecranon against the table and winced in pain.
Olecranon → It is formed from "olecranon" (from Greek "ōlekranon", meaning the elbow) which is a combination of "ōle" (meaning elbow) and "kranion" (meaning head or skull). The word refers to the bony prominence of the elbow, resembling a head at the elbow joint.
Picture the 'head' ('kranion') of the 'elbow' ('ole') — that's why olecranon refers to the bony part of your elbow.