in (the strictest) confidence

trusting that something said will not be told to anyone else.

She told me her plans in confidence, and I really can't talk to anyone about them.

• have feet on the ground
• have finger on the button
• have finger on the pulse
• have fingers in the till
• have first call on
• have first call on something
• have first crack at
• have first crack at something
• have first refusal
• have friends in high places
• have fun and games
• have going for
• have going for it
• have going for you
• have got it bad
• have got it made
• have got number
• have got someone's number
• have got the hump
• have got to be kidding
• have got to hand it to
• have got to hand it to someone
• have green fingers
• have guts for garters
• have had a bellyful of