AT THE TIP OF ONE'S TONGUE

= on the tip of one's tongue {adv. phr.} {informal} 1. Almost spoken; at the point of being said. * /It was at the tip of my tongue to tell him, when the phone rang./ * /John had a rude answer on the tip of his tongue, but he remembered his manners just in time./ 2. Almost remembered; at the point where one can almost say it but cannot because it is forgotten. * /I have his name on the tip of my tongue./