undertip 
verb (undertips, undertipping, undertipped) [with object]
Give (someone) an excessively small tip: I was so mad I undertipped the waiter at the sushi bar...
- Oh my gosh, I've been undertipping my hairstylist.
- drinking age
- drinking chocolate
- drinking fountain
- drinking game
- drinking horn
- drinking song
- drinking-up time
- drinking water
- drink like a fish
- drink someone's health
- drink someone under the table
- time sampling
- time-saving
- timescale
- time scheme
- time series
- time-served
- time-server
- time server
- time service
- time-serving
- timeshare
- time-sharer
- time-sharing
- time sheet