Division and fraction are always regarded as in connection with the total; divisions may be equal or unequal; a fraction is one of several equal parts into which the whole is supposed to be divided.

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

Example sentences

portion A small portion of ham, please, and a draught beer.
divide It's better to divide the corpse into five pieces.
fragment There's a tiny fragment that's broken off.

Popularity over time

Word	1850 → 2019	Trend
fraction		falling
portion		falling
divide		rising
fragment		steady

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

By length

4 letters: part¹
5 letters: piece¹
6 letters: divide²
7 letters: section², portion²
8 letters: fragment²
11 letters: subdivision⁴, significand

The small number after each word is its number of syllables (divide² = 2 syllables).