An essential element; a deciding point, fact, or consideration; an essential or influential circumstance.
a particular point in time; "the moment he arrived the party began"
a point with no dimension
A measurement of weight at a specific distance (moment arm) from a reference point. This measurement is used to verify the aircraft is within the Center of Gravity (CG) limits. Reference points vary between aircraft.
refers to a distance on a model forward or aft of the balance point.