This is the 7189th most frequent Russian word.
василенко
"Василенко" is a Russian surname and does not have a specific definition; it is a proper noun.
Here, 'Василенко' is used as a surname, functioning as the subject of the sentence, indicating someone's last name.
Василенко успешно провел лекцию по биологии.
Vasilyenko successfully gave a lecture on biology.
In this instance, 'Василенко' refers to a family name, representing a group of people sharing the same surname.
Семья Василенко собирает ягоды в лесу каждое лето.
The Vasilyenko family gathers berries in the forest every summer.
Here, 'Василенко' represents the signing individual, most likely the sender of the letter, indicating them as the origin of the correspondence.