quickly; swiftly; without delay
Formal or literary adverb meaning 'quickly' or 'at once'. In modern Japanese, すぐに or 早く are more common in everyday speech.
I will come at once.
long ago; already; some time ago
Formal/literary use meaning 'already' or 'long since'. Often found in classical or poetic contexts. In modern language, すでに or とっくに are more natural.
Inform me of the circumstances without delay.
I have already heard that story.
He passed away long ago.
quickly; swiftly
Derived from classical Japanese adverb 疾く (toku), from the adjective 疾し (toshi) meaning 'quick'. The kanji 疾 carries the meaning of 'swift' or 'rapid'.