Hide zoom buttons in ArcGIS

Pass in slider: false as an option when creating the map. Here is the Map Options API Reference.

map = new Map("map", {
    basemap: "streets",                 
    slider: false
}

I did it with:

on(map, "load", function () {
        map.hideZoomSlider();
    });

For anyone trying to accomplish this using the 4.x versions of the API, try the following when using the MapView (or SceneView) constructor:

var view = new MapView ({
    container: "viewDiv",
    map: map,
    ui: {
        components: [ "attribution" ]
    }
});

Source: https://developers.arcgis.com/javascript/latest/sample-code/view-disable-zoom/index.html