Sid originated as a nickname for Sidney, but we like it on its own, a la Sara Quin's and Jason Biggs and Jenny Mollen's sons. Sid Vicious, member of the band the Sex Pistols, gives this name a punk rock vibe.

There are almost the exact same number of female and male Sidneys born in the US these days, which makes Sid a perfect gender-neutral nickname. And cute for boys or girls.