mus·tard 
/ˈmʌstɚd/ noun
plural mus·tards /ˈmʌstɚd/ noun [count, noncount] 1 : a thick and spicy yellow or brownish-yellow sauce that is usually eaten with meat
▪ Would you like some mustard on your hot dog? 2 : a plant with yellow flowers, leaves that can be used for food, and seeds that are used in making mustard 3 : a brownish-yellow color — see color picture
▪ Would you like some mustard on your hot dog?
(as) keen as mustard — see 1keen
cut the mustard
informal : to be good enough to succeed or to do what is needed
▪ She tried to join the soccer team, but she couldn't cut the mustard. ▪ Now that we have computers, typewriters just don't cut the mustard anymore.
▪ She tried to join the soccer team, but she couldn't cut the mustard. ▪ Now that we have computers, typewriters just don't cut the mustard anymore.
