addresser comes from address + -er, from Old French adrecier ('to straighten, direct'), from Vulgar Latin *addirectiare, from Latin ad- ('to') + directus ('straight, direct'). Morphologically, the word is transparent: -er is attached to the older base named in the history, so the modern form packages an inherited or borrowed stem inside a later English derivative. In modern use, the noun sense is "a person who addresses or sends something to another", which keeps the etymology connected to the word's present dictionary value rather than treating it as a merely historical label. The wider word family includes related English forms such as address, addressee, showing how the same base continues to support neighboring English vocabulary. The principal historical forms in the chain include Old French adrecier, Latin directus, which anchor the explanation in named linguistic material.