JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container" id="container">
    <h1 id="finalWord"></h1>
    <input type="text" id="searchInput" placeholder="Жаргонизм">
    <button id="submitBtn">Найти жаргонизм</button>
 </div>

JavaScript

$(function () {
  var words = {
    'девушка': ['чикса', 'тёлка', 'чувиха'],
    'замечательный': ['чумовой', 'отпадный', 'классный']
  };
  
  var App = {
    
    init: function () {
      this.cacheElements();
      this.bindEvents();
    },
    
    cacheElements: function () {
      this.$container = $('#container');
      this.$finalWord = this.$container.find('#finalWord');
      this.$searchInput = this.$container.find('#searchInput');
      this.$submitBtn = this.$container.find('#submitBtn');
    },
    
    bindEvents: function () {
      this.$submitBtn.on('click', this.findWord.bind(this));
    },
    
    findWord: function (e) {
      var word = this.$searchInput.val().trim(),
          random,
          f,
          v;
      
      if (!word) return;
      
      for (var i in words) {
        if (i === word) {
          random = Math.floor(Math.random() * words[i].length);
          this.$finalWord.text(words[i][random]);
        }
      }
        
      e.preventDefault();
    }
    
  }
  
  App.init();
});