is a specific kind of: mouth, speak, talk, utter, verbalise, verbalize.

derivation: sibilant, sibilant consonant | bird, boo, Bronx cheer, hiss, hoot, raspberry, razz, razzing, snort | assibilation, sibilation | fizzle, hiss, hissing, hushing, sibilation.

is a specific kind of: emit, let loose, let out, utter.

derivation: bird, boo, Bronx cheer, hiss, hoot, raspberry, razz, razzing, snort | fizzle, hiss, hissing, hushing, sibilation | hisser | continuant, fricative, sibilant, spirant, strident.

is a specific kind of: female sibling.

is a broader term that covers: big sister | little sister | half-sister, half sister, stepsister.

is the opposite of: blood brother, brother.

derivation: sisterhood, sistership | sisterlike, sisterly, sororal.