old-fashioned

relaxed and not worried about the results of your actions.

He had a rather devil-may-care attitude towards money which impressed me at the time.

• a fine line
• a finger in every pie
• a firm hand on the tiller
• a fishing expedition
• a fish out of water
• a flash in the pan
• a flight of fancy
• a flight of fantasy
• a flight of imagination
• a flip-flop
• a fly in the ointment
• a fly on the wall
• a fool and his money are soon parted.
• a fool's errand
• a force to be reckoned with
• a foregone conclusion
• a four-letter word
• a frame of mind
• a Frankenstein's monster
• a free agent
• a free-for-all
• a free ride
• a free spirit
• a French letter
• a friend in need.