One potential synonym for "ft-l" is "foot-pounds," as this measurement describes the amount of force required to move an object one foot in distance. Other possible synonyms may depend on the specific context in which the measurement is being used, such as in the case of torque or other types of mechanical work. Some other terms that may be used in conjunction with "ft-l" could include "work units," "energy units," or "unit of work." Ultimately, the use of appropriate synonyms can help to clarify communication and ensure that all parties fully understand the meaning behind technical terminology.