16 letters
- southwesternmost26
- sphygmomanometer35
- stadtholderships26
- stereoisomerisms22
- stereomicroscope28
- stereophonically29
- stereoregularity22
- stereoscopically29
- subversivenesses29
- sufferablenesses28
- superbillionaire26
- superbureaucrats28
- supercalendering29
- superciliousness26
- supercomfortable33
- supercompetitive33
- supercorporation27
- superenciphering32
- superfecundation30
- superficialities27
- supergovernments31
- superheavyweight35
- superheterodynes26
- superhumannesses28
- superimpositions27
- superincumbently35
- superintelligent26
- superintendences27
- superintensities22
- supermillionaire26
- supernaturalisms26
- supernaturalists23
- supernaturalness24
- supernormalities25
- superparasitisms26
- superpatriotisms26
- superphenomenons31
- superromanticism30
- supersaturations22
- supersensitively28
- supersensitivity27
- superserviceable31
- supersexualities29
- superspecialists27
- superspecialized37
- superspectacular31
- superspeculation29
- superstimulating28
- supersubstantial26
- teleconferencing31
- teratocarcinomas26
- teratogenicities22
- terminablenesses25
- terminologically30
- territorialities17
- territorializing29
- thermodynamicist31
- thermolabilities26
- thermometrically31
- thermoperiodisms28
- thermoplasticity30
- thermoregulating28
- thermoregulation26
- thermoregulators25
- thermoregulatory27
- thermoremanences29
- thermostatically28
- transliterations19
- transmissometers23
- trifluoperazines34
- turbomachineries29
- ultraliberalisms26
- ultramarathoners24
- ultrasonographer26
- unalterabilities23
- uncharacteristic29
- uncommercialized41
- underachievement32
- underappreciated29
- undercapitalized36
- underdevelopment32
- underemphasizing39
- underemployments32
- underestimations23
- underinvestments28
- undernourishment27
- underproductions28
- underrepresented24
- undersecretaries22
- underutilization31
- undifferentiated27
- universalization33
- unmannerlinesses25
- unreservednesses24
- ununderstandable27
- verifiablenesses28
- videoconferences32
- vociferousnesses28
- vulnerablenesses28
- waterproofnesses26
- watertightnesses24
- weatherabilities25
- weatherboardings28
- weatherproofness28