Fast

Adjective: Moving, happening, or doing something quickly

-- Fast cars

Adverb: Moving or happening quickly

-- We ran as fast as we could.

Adverb: In a firm or tight way

-- He tried to get away, but she held him fast.

Adjective: If a clock or watch is fast, it shows a time that is later than the correct time.

-- My watch is five minutes fast.

Verb: To eat nothing, or much less than you usually eat for a period of time

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