What is the duty of the court to provide a jury with a definition of a common law term?

After informing counsel, the court is required to respond to jury questions "on any point of law arising in the case." ( 1138.) "The court has a primary duty to help the jury understand the legal principles it is asked to apply. [Citation.] Where the original instructions are themselves full and complete, the court has discretion under section 1138 to determine what additional explanations are sufficient to satisfy the jury's request for information. [Citation.] Indeed, comments diverging from the standard are often risky. " (People v. Beardslee (1991) 53 Cal.3d 68, 97.) "This does not mean the court must always elaborate on the standard instructions." (Ibid.) But " '[a] definition of a commonly used term may nevertheless be required if the jury exhibits confusion over the term's meaning.' " (People v. Solis (2001) 90 Cal.App.4th 1002, 1015 [citations omitted].)