This is the 651st most frequent Polish word.
trochę
A little; somewhat; a bit.
Here, 'trochę' is used as a quantifier to indicate a small amount of 'time'.
Potrzebuję jeszcze trochę czasu.
I need a bit more time.
In this context, 'trochę' is used to modify the adjective 'zimno' (cold), suggesting that the level of coldness is moderate or not severe.
Na dworze jest trochę zimno.
It is a bit cold outside.
'Trochę' functions as a quantifier here, suggesting eating a small portion of 'salad'.