penknife
UK[ˈpɛnnaɪf]US[ˈpɛnnaɪf]
n
A small knife with a blade that folds into the handle.
Morpheme Breakdown
pen
knife
pen
knife
cutting instrument
Etymology
The word "penknife" is a compound formed from two Old English elements, though the first part has a Latin origin. Historically, a penknife was a small, sharp knife used for cutting and sharpening quill pens, which were made from feathers. The term "pen" itself derives from the Latin "penna," meaning "feather," reflecting the original writing instrument. Over time, as metal nibs and later ballpoint pens replaced quills, the object evolved but retained its name, now referring generally to any small folding pocket knife.
Analysis
Structure: pen + knife
pen (Latin, via Old French, meaning "feather" or "quill pen"); knife (Old English, meaning "cutting instrument")
Examples
He used a penknife to sharpen the pencil.
The old penknife had a bone handle and a single, sharp blade.
Always be careful not to cut yourself when closing a penknife.