A second type of complex noun consists of a verb followed by a suffix meaning one who does or thing which does. The English suffix -er (as in builder "one who builds'' or toaster "thing which toasts'') is a rough equivalent. In Klingon, the suffix is -wI'. It occurs, for example, in baHwI' gunner, which consists of the verb baH fire (a torpedo) plus -wI' one who does. Thus, baHwI' is literally "one who fires [a torpedo].'' Similarly, So'wI' cloaking device comes from the verb So' cloak plus -wI' thing which does. So'wI' is a "thing which cloaks.''

A noun formed by adding -wI' to a verb is a regular noun, so it may be used along with another noun to form a compound noun. For example, tIjwI'ghom boarding party comes from tIjwI' boarder plus ghom group; and tIjwI' comes from tIj board plus -wI'.

In reference to inanimate objects, this suffix means "thing which does" (joqwI' thing which flutters) or "thing which is used for" (nanwI' thing which is used to gouge). 

In reference to animate beings, this suffix means "one who does" (baHwI' one who fires) or "one who is" (pujwI' one who is weak).