I. wake up phrasal verb (see also wake)

1. to stop sleeping, or to make someone stop sleeping:
James usually wakes up early.
wake somebody ↔ up
I’ll wake you up when it’s time to leave.

2. to start to listen or pay attention to something:
Wake up (=give me your attention) at the back there!

3. wake up and smell the coffee American English spoken used to tell someone to recognize the truth or reality of a situation

[TahlilGaran] Dictionary of Contemporary English ▲

II. wake¹ S2 W3 /weɪk/ (also wake up) verb (past tense woke /wəʊk $ woʊk/, past participle woken /ˈwəʊkən $ ˈwoʊ-/) [intransitive and transitive]
[Language: Old English; Origin: wacan 'to wake up' and wacian 'to be awake']
to stop sleeping, or to make someone stop sleeping:
When she woke, the sun was streaming through the windows.
Try not to wake the baby.
wake to
Nancy woke to the sound of birds outside her window (=she heard birds singing when she woke).
wake up phrasal verb

1. to stop sleeping, or to make someone stop sleeping:
James usually wakes up early.
wake somebody ↔ up
I’ll wake you up when it’s time to leave.

2. to start to listen or pay attention to something:
Wake up (=give me your attention) at the back there!

3. wake up and smell the coffee American English spoken used to tell someone to recognize the truth or reality of a situation
wake up to something phrasal verb
to start to realize and understand a danger, an idea etc:
It’s time you woke up to the fact that it’s a tough world.

[TahlilGaran] Dictionary of Contemporary English ▲