Is it permissible in American courts to require the prosecutor to unambiguously define "hacker" before answering? If not, can you feign ignorance of the defini

Is it permissible in American courts to require the prosecutor to unambiguously define "hacker" before answering? If not, can you feign ignorance of the definition and explain that you are thus literally incapable of providing an honest & informed answer; and since you are under oath, require a definition before answering?