As regards practical matters, uncertainty applies to the unknown or undecided; doubt implies some negative evidence. Suspense regards the future, and is eager and anxious; uncertainty may relate to any period, and be quite indifferent.

J. C. Fernald, English Synonyms and Antonyms (1914)

Example sentences

doubt There's a blind man looking for a shadow of doubt.
hesitation Mary jumped into the icy water without hesitation.
suspense The two part episode's cliffhanger had me in suspense.
distrust True love knows neither suspicion nor distrust.
insecurity Gazans are facing high levels of food insecurity.

Popularity over time

Word	1850 → 2019	Trend
uncertainty		rising
doubt		steady
hesitation		rising
suspense		steady
distrust		steady
insecurity		rising

Use in printed books, per decade from 1850 to 2019.

By length

4 letters: maze¹
5 letters: doubt¹, peril²
6 letters: chance¹
7 letters: dubiety
8 letters: suspense², distrust², quandary³, fortuity
9 letters: uncertain³, ambiguity⁵, obscurity⁴, vagueness²
10 letters: insecurity⁵, hesitation⁴
11 letters: contingency⁴, inconstancy⁴, dubiousness, incertitude
12 letters: irregularity⁶, irresolution, uncertainity, doubtfulness, noncertainty
13 letters: uncertainness
14 letters: precariousness, capriciousness, indefiniteness, changeableness

The small number after each word is its number of syllables (peril² = 2 syllables).

In other languages

Français: incertitude
Italiano: incertezza
Español: incertidumbre
Deutsch: Unsicherheit
Català: incertesa