Etymology

A “space” is an area or place. If you “space out”, you mentally drift away from the place you are currently placed, and go off into empty, dreamy space as shown in the above cartoon.

Space out

Verb phrase

• place a space, hit a carriage return
• become absent-minded,
  lose all concentration,
  slip out of normal consciousness,
  have nothing on your mind,
  be heedless,
  listen to someone with unhearing ears,
  stare fixedly at nothing in particular with consciousness miles away

Synonyms

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• get doped
• be empty-headed
• be dull-witted
• remain preoccupied
• be reckless
• be thoughtless
• zone out

Usage

I spaced out while my teacher talked about the mid-term exam.

After working on my hormwork for five hours straight, I spaced out in front of my computer.

Space-out

Noun

• a person who does not understand the situation at hand

Synonyms

1. dumbbell
2. fool
3. muggins
4. sap
5. saphead
6. tomfool
7. weakling

Usage

What a space-out, she doesn't even know what's going on!

After “The Fifth Elephant”, I tried to content myself with magazines and newspapers but by last night, I grew restless again. I took a library book off the bedroom shelf and started to read, only to find that I’d already read it. What a space-out I am! I didn’t remember that I’d read Bruce Sterling’s Distraction last year, even after reading the inside flap.

Spaced-out

Adjective

• dazed by the use of alcohol or narcotic drugs

Synonyms

1. bedazed
2. dazed
3. doped
4. drugged
5. drunk
6. foggy
7. groggy
8. narcotized
9. stunned
10. stupefied
11. stuporous

Usage

This pill called “ecstasy” has a spaced-out effect.

Jimmy remained spaced　out for quite a while after taking an ecstasy pill.

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