feed (one) a line

1. To tell an actor what to say. In this usage, the phrase is often used in the plural ("feed one (one's) lines"), and "line" refers to a line of dialogue in the script. I'm sorry, I can't remember a word of this scene—can someone please feed me my lines? We've had to feed her her lines at every rehearsal this week. At what point do we ask her understudy to take over? A: "Hold on. Bill, you know you say something when you enter this scene, right?" B: "Aww, geez. Could someone feed me a line, please?"

2. To speak deceptively to one. In this usage, "line" refers to a prepared response, perhaps one intended to be what the listener wants to hear. Don't feed me a line, tell me the truth—what's the real reason you missed my party? Mike fed that poor girl some line about her beauty that we've all heard out of him a million times. Gross. How exactly did Mom's vase get broken? Don't feed me a line, I'm not gonna tell on you.

feed someone a line

1. Also, feed someone lines. Cue an actor with his or her next line (or lines), or tell someone what to say, as in Some contestants become tongue-tied, so someone has to feed them a line, or Eric still has trouble learning a part; he needs someone to feed him his lines.

2. Also, hand someone a line. Lead someone on, deceive with glib or exaggerated talk. For example, He really fed them a line about his important new position, or Don't hand me a line-I know exactly how much you paid for it. [Early 1900s]