The difference between past and passed is that Passed is always a verb, and past is never used as a verb.
Passed is the past tense of pass, which means to move in a specified direction or to leave behind in proceeding. Past can be an adjective, a noun, a preposition, or an adverb, and we'll get into its various definitions below.
Passed vs. past are homophones, which means the words sound identical but they have different meanings and spellings.
Definitions of past vs. passed
We're pulling straight from Merriam-Webster for these definitions of passed and past.
passed (v., past tense of the verb pass): to move, proceed, go; to go away, depart; to die
She passed the other runners in the race and came in first place.
past (adj.): ago; having existed or taken place prior to the present
I saw my best friend this past weekend.
past (prep.): beyond the age for or of, after; at the farther side of, beyond; beyond the capacity, range, or sphere of
My class starts at half past five.
past (n.): a time gone by; something that happened or was done in the past; the past tense of a language; a past life, history, or course of action
His past was shrouded in mystery.
past (adv.): so as to reach and go beyond a point near at hand
I drove past my favorite house in the neighbourhood.
Difference between passed vs. past
As you can see, there are a lot of definitions for the word past, but none of them are verbs. However, the singular definition of passed is a verb.
That is the biggest difference between the two words, and the clue that can help you the most when you're deciding which one to use. If you need a verb, use passed. If you don't, use past.
When in doubt, check it out. Use QuillBot's Grammar Checker to make sure you're using the right word.
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