DaghIjlu'chugh jachqu' maQ
If you're scared, the sign/omen yells (loudly)
(Okrand's suggested translation for "Fear speaks very loud")

It is not known if this noun can refer to any kind of physical "sign", or if it only refers to happenings or things that can be interpreted as a sign. Clarification by Okrand is needed

Included below is some examples of types of signs on Klingon buildings. These may not be actual maQ. 

As an example of a text on a sign, the signs at or on or near building door may read 'el (for "entrance") and 'elHa' (for "exit"). These are shortened (for sign purposes) from 'elmeH He and 'elHa'meH He.