splurge
n. B2 Upper Intermediate US //ˈspɫɝdʒ// UK //splˈɜːdʒ// splurge
n. a period of time when you spend a lot of money on things you do not really need. It is often a way to treat yourself after a long time of saving.
n. a period of excessive spending on non-essential items.
I am going on a shopping splurge this weekend.
After months of strict budgeting, she decided to have a small splurge on a new piece of furniture.
The company's annual splurge on office amenities, such as gourmet coffee and ergonomic chairs, is seen by some as a necessary investment in employee morale.
Possibly from a blend of splash + surge, originally US. According to the OED, onomatopoeic.