What does "thousand" mean?

Thousand: Hence, indefinitely, a great number. A thousand shall fall at thy side, and ten thousand at thy right hand. Ps. xci.

Additional senses

  1. 2.Note: The word thousand often takes a plural form. See the Note under Hundred.
  2. 3.A symbol representing one thousand units; as, 1,000, M or CI.
  3. 4.Consisting of ten hundred; being ten times one hundred.
  4. 5.Hence, consisting of a great number indefinitely. "Perplexed with a thousand cares." Shak.

Sources