JSFiddle - React, Tailwind, and code Playground

JavaScript

var array = [
    ["a", "b", "c"],
    ["a", "b", "c"],
    ["a", "b", "c"]
];


var idx = 2;
for (var i = 0; i < array.length; i++) {
    array[i].splice(idx, 1);
}

console.log(array);