son*
Here are some words that match your criteria:

- Son
- son of a bitch
- son-in-law
- sonant
- sonar
- sonata
- sonata form
- Sonchus
- Sonchus oleraceus
- Sondheim
- sone
- song
- song and dance
- Song dynasty
- Song of Solomon
- Song of Songs
- song sparrow
- song thrush
- songbird
- songbook
- songful
- songfulness
- Songhai
- songlike
- songster
- songstress
- songwriter
- sonic
- sonic barrier
- sonic boom
- sonic delay line
- sonic depth finder
- sonnet
- sonneteer
- sonny
- sonny boy
- Sonny Liston
- sonogram
- sonograph
- sonography
- sonometer
- Sonora
- Sonora gum
- Sonora lac
- Sonora semiannulata
- Sonoran Desert
- Sonoran lyre snake
- Sonoran whipsnake
- sonority
- sonorous
- sonorously
- sonorousness
- sonsie
- sonsy
- Sontag