| ACTINOIDS | • actinoids n. Plural of actinoid. • ACTINOID n. any element of a group from element number 89 (actinium) upwards, also ACTINIDE. |
| AMMONOIDS | • ammonoids n. Plural of ammonoid. • AMMONOID n. the coiled shell of an extinct mollusk, also AMMONITE. |
| CATENOIDS | • catenoids n. Plural of catenoid. • CATENOID n. the surface generated by rotating a catenary about its axis. |
| ECHINOIDS | • echinoids n. Plural of echinoid. • ECHINOID n. a sea urchin, also ECHINUS. |
| HOMINOIDS | • hominoids n. Plural of hominoid. • HOMINOID n. a member of the superfamily Hominoidea, comprising man and modern apes and their extinct ancestors, also HOMINIAN. |
| HUMANOIDS | • humanoids n. Plural of humanoid. • HUMANOID n. something having human form. |
| MELANOIDS | • melanoids n. Plural of melanoid. • MELANOID n. someone suffering from melanosis. |
| PARANOIDS | • paranoids n. Plural of paranoid. • PARANOID n. someone suffering from paranoia. |
| PYRENOIDS | • pyrenoids n. Plural of pyrenoid. • PYRENOID n. a protein body of certain lower organisms. |
| RESINOIDS | • resinoids n. Plural of resinoid. • RESINOID n. a resinous substance. |
| RETINOIDS | • retinoids n. Plural of retinoid. • RETINOID n. a compound analogous to vitamin A. |
| SOLENOIDS | • solenoids n. Plural of solenoid. • SOLENOID n. a cylindrical wire coil acting as a magnet when charged. |
| SPHENOIDS | • sphenoids n. Plural of sphenoid. • SPHENOID n. a wedge-shaped bone. |
| TECHNOIDS | • technoids n. Plural of technoid. • TECHNOID n. a technician. |