JSFiddle - React, Tailwind, and code Playground

HTML

<table>
    <tr class="item" id="1">
            <td class="item-name-cell">Товар один<td>
            <td class="size-cell">5</td>
            <td class="under_order">Под заказ</td>
    </tr>
    <tr class="item" id="2">
            <td class="item-name-cell">Товар два<td>
            <td class="size-cell">5</td>
            <td class="ok">В наличии</td>
    </tr>
</table>

JavaScript

$('table').find('td.under_order').closest('tr').hide();