to sterilize /ˈstɛrɪlʌɪz/ /ˈstɛrɪlʌɪz/
to castrate /kæˈstreɪt/ /kæˈstreɪt/
to spay /speɪ/ /speɪ/
to neuter /ˈnuːtər/ /ˈnjuːtə/