/ ˈpɔːʃn; NAmE ˈpɔːrʃn/ noun , verb
■ noun
1.
one part of sth larger :
a substantial / significant portion of the population
Only a small portion of the budget is spent on books.
The central portion of the bridge collapsed.
2.
an amount of food that is large enough for one person :
a generous portion of meat
She cut the cake into six small portions.
3.
[ usually sing. ] a part of sth that is shared with other people
SYN share :
You must accept a portion of the blame for this crisis.
■ verb
[ vn ] portion sth (out) to divide sth into parts or portions :
The factory portions and packs over 12 000 meals a day.
Land was portioned out among the clans.
••
WORD ORIGIN
Middle English : from Old French porcion , from Latin portio(n-) , from the phrase pro portione in proportion.