What does "addend" mean?

Addendum, any one of two or more numbers or other terms that are to be added together.

Addend

Common synonyms include: addends, algebraic term, argument, count components, element, element summed.

/ˈæd.ɛnd/ noun, verb

noun, verb ·Uncommon ·Advanced level

Noun

1
Addendum, any one of two or more numbers or other terms that are to be added together.
2
a number that is added to another number (the augend) wordnet
3
A moiety added to another molecule.

Verb

Short for addendum, by surface analysis, add + -end.