to drop (someone) a line: to write a note to someone (S)
to stop by: to visit or stop somewhere briefly (also: to drop by, to drop in on)
To drop by and to drop in on are used for visits that are unplanned or unexpected.
to hold on: to grasp tightly or firmly; to wait, to be patient (also: to hang on)
The second definition is often used when someone is talking on the telephone.
to name after: to give the same name as another(S)
to stress out: to worry, be anxious, of reel stress; to cause to worry, be anxious, or feel stress (S)
to take by surprise: to surprise, to amaze, to astonish(S)
A noun or pronoun usually divides this idiom.
to be well-off: to have enough money to enjoy a comfortable life, to be rich (also: to be well-to-do)
to be better off: to be in a more favorable condition or situation
The opposite of this idiom is to be worse off.