TypeError: $ (...). Tooltip is not a function

Question

TypeError: $ (...). Tooltip is not a function

I get

TypeError: $ (...). Tooltip is not a function

in the jquery file in which I initialize the tooltip () function when using lightbox2 with loading.

$(function() {
  $('[data-toggle="tooltip"]').tooltip({
      html: true
  });
});

<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>
        <script src="bootstrap/js/bootstrap.js"></script>
        <script src="main.js"></script>
</head>
<body>
  <script src="lightbox-plus-jquery.min.js"></script>
</body>