What is a Close-by Word?™

This puzzle is done in honor of JLee's wonderful Words and Phrases series of puzzles. JLee must be really proud of us now.

If a word has a certain property, I call it a Close-by Word™.

In each of sentences below, one is a Close-by Word™ and one is not. Cases and fonts have no bearing in the property of the word. Sentences are for context only. Only knowledge of English is required.

1. The (elf / dwarf) fights an army.
2. The device (slashes / reduces) fatalities.
3. We will (wax / defeat) the competition.
4. A young man (created / invented) a time machine.
5. I wish I was (driving / flying) across the country.
6. People should not (jaywalk / cross) the street.
7. Taxes will (increase / decrease) over time.
8. The house has this (classic / modern) look to it.
9. The shadow will (loom / tower) over us.
10. Nothing is as (strange / queer) as that.

What is a Close-by Word™?

• Be careful not to overuse this problem type. We've had problems with that in the past. – Joe Z. Aug 12 '15 at 1:59
• @JoeZ. Can't we make a tag for them? Like phrase-tm and word-tm? – Bojidar Marinov Aug 12 '15 at 11:42
• @BojidarMarinov Making a tag doesn't solve the problem that too many problems of the tag type are being created at once. – Joe Z. Aug 13 '15 at 3:20
• @JoeZ. But it makes them easily searchable/filterable, and thus they are less a nuisance. (Yeah, it won't solve the problem, but the only other solution I see is to close them as dupes/something) – Bojidar Marinov Aug 13 '15 at 8:43
• Right, the filtering. I suppose that's at least helpful. – Joe Z. Aug 14 '15 at 0:10

A close-by word is

A word whose ending letter is exactly one after its starting letter in the alphabet.

Examples given:

Y: Elf (e/f) N: Dwarf (d/f)
Y: Reduces (r/s) N: Slashes (s/s)
Y: Wax (w/x) N: Defeat (d/t)
Y: Created (c/d) N: Invented (i/d)
Y: Flying (f/g) N: Driving (d/g)
Y: Jaywalk (j/k) N: Cross (c/s)
Y: Decrease (d/e) N: Increase (i/e)
Y: Modern (m/n) N: Classic (c/c)
Y: Loom (l/m) N: Tower (t/r)
Y: Queer (q/r) N: Strange (s/e)

• Man, you log on to Puzzling you open up the latest tm, you finally see you can solve it, then you scroll down... Well done +1 for expedience. – Going hamateur Aug 12 '15 at 2:36
• @Goinghamateur the question is, how many of these do I have to slave over before I solve one? The answer is...something like 15, I guess! – Bailey M Aug 12 '15 at 2:40
• Good job Bailey. i knew you'd get one eventually. – JLee Aug 12 '15 at 3:12
• @JLee one of these days I'll get one of yours...just you wait... – Bailey M Aug 12 '15 at 3:12
• oh I wouldn't be surprised at all – JLee Aug 12 '15 at 3:14