The term 'small beam' can be broken down into two crossword solutions: GRIN (4 letters) and RAY (3 letters). A GRIN is a facial expression that typically involves both the corners of the mouth being turned up and the eyes crinkling. It is often used to express amusement, joy, or pleasure. A RAY is a line or beam of light that travels in a straight line away from its source. In this context, a small beam could refer to a narrow beam of light, such as a laser or flashlight.