def decrypt(num_keys, keylist, wordlist, word_to_idx, words):
    """Encrypt words using OTP word indexes."""
    if len(words) > num_keys:
        raise ValueError('Number of input words exceeds key length')
    result = []
    for i in range(0, len(words)):
        c = words[i]
        c_i = word_to_idx[c]
        k = keylist[i]
        m_i = (c_i - k) % len(wordlist)
        result.append({'message': wordlist[m_i], 'ciphertext': wordlist[c_i]})
    return result
