noun
plural rails
[count] a bar that goes from one post or support to another and that is used to form a barrier
a bar used to hang something from
[count] :one of the bars of steel that form a train's track - usually plural
[noncount] :1railroad
go off the rails
informal :to lose control and start to behave in a way that is not normal or acceptable
verb
rails; railed; railing
[+ obj] :to use rails to create a barrier around or at the edge of (something) - usually + off
verb
rails; railed; railing
[no obj] formal :to complain angrily about something