Definition

A person of questionable character or reliability; someone who seems suspicious or untrustworthy. Can also mean a situation or plan that feels risky or poorly thought out.

Example Usage

I don't trust that guy—he's kind of a sketch.

Origin

American slang, likely derived from the adjective 'sketchy' (incomplete or rough), applied to people who seem like they lack clear moral outlines.

Fun Fact

In improv comedy, a 'sketch' is a short comedic scene, but the slang usage (meaning a suspicious person) developed separately in informal speech.

Source: Definition backfill (hailey)