That’s correct. It has a specific meaning dealing with baptized communities who are separated. Evangelization and just plain old charity are not necessarily ecumenism, although there is overlap. Evangelization and charity is applied to everyone inside and outside the Church, with or without faith in Jesus.
From the CCC:
**Paragraph 3. The Church Is One, Holy, Catholic, and Apostolic
**
811 "This is the sole Church of Christ, which in the Creed we profess to be one, holy, catholic and apostolic."256 These four characteristics, inseparably linked with each other,257 indicate essential features of the Church and her mission. The Church does not possess them of herself; it is Christ who, through the Holy Spirit, makes his Church one, holy, catholic, and apostolic, and it is he who calls her to realize each of these qualities.
812 Only faith can recognize that the Church possesses these properties from her divine source. But their historical manifestations are signs that also speak clearly to human reason. As the First Vatican Council noted, the "Church herself, with her marvelous propagation, eminent holiness, and inexhaustible fruitfulness in everything good, her catholic unity and invincible stability, is a great and perpetual motive of credibility and an irrefutable witness of her divine mission."258
I consider being Apostolic to mean bringing Jesus to the world. When one does an act of charity, that is bringing Jesus to the world. Maybe not in word, but in deed.
Bringing our fruitfulness to the world is an irrefutable witness of the Church’s diving mission.