Float voltage. Float voltage is the voltage at which a battery is maintained after being fully charged to maintain that capacity by compensating for self-discharge of the battery. The voltage could be held constant for the entire duration of the cell's operation (such as in an automotive battery) or could be held for a particular phase of charging by the charger.
Definition of sup. supped. ; supping. transitive verb. : to take or drink in swallows or gulps. intransitive verb. chiefly dialectal : to take food and especially liquid food into the mouth a little at a time.
Suf is a variant of sub, below or under, so a suffix is something fastened underneath something else (in this case, behind the root). By learning the common roots and prefixes (and a few suffixes) you will be able to discern the meaning of many new words almost immediately. (But do look them up for confirmation.) Take the word abject, for example.