slow up
[noun]
Synonyms: slowdown, slack, slackening

[TahlilGaran] English Synonym Dictionary ▲

slow² S3 W2 (also slow down/up) verb [intransitive and transitive]
to become slower or to make something slower:
Her breathing slowed and she fell asleep.
Ian slowed up as he approached the traffic lights.
slow down phrasal verb

1. to become slower or to make something slower:
Growth in sales has slowed down.
slow somebody/something ↔ down
The ice on the road slowed us down.

2. to become less active or busy than you usually are:
It is important to slow down, rest, and eat sensibly.

[TahlilGaran] Dictionary of Contemporary English ▲

slow up
to cause someone or something to reduce speed
The factory manager decided to slow up production because of problems in the shipping department.

[TahlilGaran] English Idioms Dictionary ▲

slow up
v.
1. To go more slowly.
The truck slowed up as it approached the toll gate.
Construction on the road slows up traffic.
2. To become less busy.
Business slows up at the stores after Christmas.

[TahlilGaran] English Idioms Dictionary ▲