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