outlet - an opening that permits escape or release; he blocked the way out; the canyon had only one issue. exit, way out, issue. opening - a vacant or unobstructed space that is man-made; they left a small opening for the cat at the bottom of the door.
Differences between grep, pgrep, egrep, and fgrep (Linux): grep grep is an acronym that stands for Global Regular Expressions Print. grep is a program which scans a specified file or files line by line, returning lines that contain a pattern. A pattern is an expression that specifies a set of strings by interpreting characters as meta-characters.
You can use git branch --contains to list all the branches descended from the tip of develop, then use grep to make sure feature is among them. If it is among them, it will print  feature to standard output and have a return code of 0. Otherwise, it will print nothing and have a return code of 1.