Be on the cold, small, etc. side - Idioms by The Free Dictionary
be on the cold, small, etc. side
be on the (something) side
To partially have some quality, typically a negative one. An adjective precedes "side." The dress is beautiful, but it's just a little on the expensive side for me. A: "Do you like what you ordered?" B: "It's good, just a little on the salty side."
be (a bit, a little, etc.) on the ˈcold, ˈsmall, etc. side (informal) be slightly too cold, small, etc: These boots are a bit on the big side, but they’re quite comfortable. ♢ It’s a little on the cold side this morning.