Definitions for nail down
nail down, nail, peg(verb)
succeed in obtaining a position
"He nailed down a spot at Harvard"
pin down, peg down, nail down, narrow down, narrow, specify(verb)
"I cannot narrow down the rules for this game"
finalize, finalise, settle, nail down(verb)
make final; put the last touches on; put into final form
"let's finalize the proposal"
to attach with nails
to make something (e.g. a decision or plan) firm or certain