This sample demonstrates how to remove the tick marks from the zoom level slider. You do this by setting the sliderLabel to null in esriConfig:
esriConfig.defaults.map.sliderLabel = null;<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no"> <title>Map Slider No Labels</title> <link rel="stylesheet" href="https://js.arcgis.com/3.46/dijit/themes/claro/claro.css"> <link rel="stylesheet" href="https://js.arcgis.com/3.46/esri/css/esri.css"> <style> .esriLargeSliderTicks { display: none; } </style> <script src="https://js.arcgis.com/3.46/"></script> <script> dojo.require("esri.map"); function init() { var map = new esri.Map("map", { center: [-68.906, 28.922], zoom: 3, sliderStyle: "large" }); map.addLayer(new esri.layers.ArcGISTiledMapServiceLayer("https://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer")); } dojo.ready(init); </script> </head> <body class="claro"> <div id="map" style="width:1024px; height:512px; border:1px solid #000;"></div> </body> </html>