speed_up has definitions from the field of grammar
1
[ verb ] move faster

Examples

"The car accelerated"

Used in print

(The Department of State: A Fresh Look at the...)

If there is anything which we can do in the executive_branch of the Government to speed_up the processes by which we come_to decisions on matters on_which we must act promptly , that in itself would be a major contribution to the conduct of our affairs .

(Edward Streeter, The Chairman of the Bored....)

Could it be that it speeded_up for the aged in some mysterious way , as if a bored universe were skipping through the end of the chapter just to get_it_over_with ?

2
[ verb ] (grammar) cause to move faster

Synonyms

speed accelerate

Examples

"He accelerated the car"

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