What does f stand for?

Failure

A rupture, break, or disintegration of a metal or part of an HVAC system. OR A general term used to imply that a part in service (a) has become completely inoperable, (b) is still operable but incapable of satisfactorily performing its intended function or © has deteriorated to the point that it has become unreliable or unsafe for continued use. The inability of a system or component to perform its required functions within specified performance requirements.

Fashion

Female

Metal tubes used to keep roof gutters "open". Long nails are driven through these tubes and hold the gutters in place along the fascia of the home. OR Any part, such as a nut or fitting, into which another (male) part can be inserted. Internal threads are female.

Fraction

Front

A boundary between two different air masses. The difference between two air masses sometimes is unnoticeable. But when the colliding air masses have very different temperatures and amounts of water in them, turbulent weather can erupt. The boundary between two air masses.

Father

The male parent. One who originates. For example, "Wilhelm Roentgen is considered the father of radiology." To produce offspring as a male. To provide paternal protection and guidance to children.

Free

Said of a vessel under sail when she has wind abaft the beam. Legally, used as indicating that no responsibility attaches to a named party in specified circumstances

Freighter

Aircraft designed to exclusively carry cargo. Cargo can also be transported in the hold of passenger planes.

Frederick