›to make someone give you exact details or a firm decision about something: nail sb down on sthWe've been trying to nail them down on the specific points of the agreement for the past six months.nail sb down to sthThings are getting urgent so we need to nail them down to a delivery date.
New words are entering the language all the time. A few of these are completely new and original coinages, but the vast majority are based on the existing stock of words in some way, for example by using affixes (prefixes and suffixes). These can have the effect of changing the meaning of the
predicting the optimum date to buy a plane ticket, especially on a website or using an app A handful of new and updated websites and apps are trying to perfect the art of what’s known as farecasting – predicting the best date to buy a ticket.