Which term is indicated by the abbreviation DLY?

The term represented by the abbreviation DLY is "Delay." In military terminology, particularly in artillery operations, which include the use of howitzers like the M119A3, understanding delay is essential for calculating firing solutions. Delay can refer to the timing adjustments made in firing the weapon to account for various factors, such as the speed of the projectile and target movement. This involves synchronizing the detonation of the round with the expected position of the target at the time of impact.

The other terms may be relevant in different contexts but do not specifically relate to the abbreviation DLY in the same way. For instance, "Dilution" typically refers to making a substance less concentrated, which is not applicable here. "Duty Limb" is not a recognized military acronym in this context, as it may pertain to specific roles or physical condition descriptions rather than artillery practices. "Disabling" implies rendering something non-functional, which again does not pertain to the concept or application of timing and coordination that "Delay" encompasses within artillery operations.