IPA: /ˌvaɪəˈlɒnʧəlɪst/
KK: /vaɪəˈlɒnʧəlɪst/
A person who plays a string instrument called the violoncello, which is similar to a cello.
The violoncellist performed beautifully at the concert last night.
**Violoncellist** → It is formed from "violoncello" (from Italian, meaning small viola) and "-ist" (meaning one who practices or is concerned with). The word refers to a person who plays the violoncello, a string instrument.
Think of someone who plays a 'small viola' ('violoncello') — the '-ist' indicates they are a person who practices that art.
No commonly confused words.