Formidable is a word of more dignity than dangerous, and suggests more calm and collected power than terrible; formidable is less overwhelming than tremendous. A loaded gun is dangerous; a park of artillery is formidable; a charge of cavalry is terrible; the full shock of great armies is tremendous.

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

Example sentences

huge Yesterday I went to the zoo and saw a huge walrus.
enormous She lives alone in a house of enormous dimensions.
terrific "You look terrific. Did you lose weight?" "I wish."
phenomenal He lifted the car with his phenomenal strength.
terrible Terrible shooting broke out the night before last.
awful I think it's awful, that they're spreading rumors.

Popularity over time

Word	1850 → 2019	Trend
tremendous		falling
huge		rising
enormous		steady
terrific		rising
phenomenal		steady
terrible		rising

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

By length

3 letters: big¹
4 letters: huge¹, dire¹
5 letters: large¹, grand¹, awful²
6 letters: horrid²
7 letters: fearful², howling², direful, tremend
8 letters: terrible³, horrible³, enormous³, shocking², terrific³, horrific³, dreadful², gigantic³, rattling², wondrous²
9 letters: wonderful³, fantastic³, marvelous³, appalling³, frightful²
10 letters: phenomenal⁴, formidable⁴, horrifying⁴, marvellous³, resounding³, prodigious³, stupendous³, gargantuan⁴
11 letters: elephantine⁴

The small number after each word is its number of syllables (awful² = 2 syllables).