• sore spot, spot, tender spot, underbelly
• delicate piece of machinery
• to put one's finger on a weak spot
• to appeal to the emotions
• to tread on delicate ground
• irritability, irritableness, rawness, responsiveness, sensibility, sensitiveness, sensitivity, sentiment, soreness, susceptibility, touchiness
• to be hard hit, to get home, to hit home, to strike home
• to cut sy to the quick, to sting sy to the quick
• to bear hard on sy, to come hard on sy, to come home to sy, to cut sy to the quick, to get home on sy, to go home to sy, to sting sy to the quick
• highly strung, over-sensitive, sensitive, supersensitive