Semicon rhymes with:
digicon, ethicon, helicon, lexicon, logicon, oerlikon, polysilicon, technicon, alarcon, catchacan, comecon, digicon, econ, emoticon, ethicon, farrakhan, helicon, lexicon, logicon, midcon, nikon, oerlikon, planecon, polysilicon, technicon, walk-on, yukon
Semicon sounds like:
samsom, samson, san-juan, sang-gon, sanguine, sanjuan, sansom, sanson, sansone, sanzone, schenken, senseney, shamanism, shangkun, shanken, shankman, shawinigan, shenanigan, shenkman, shenzhen, siemsen, simenson, simison, simkin, simonsen, simonson, simonsson, simson, singin', skonieczny, snecma, sonnenschein, sunken, sunshine, sunshiny, swanigan, swanson, swensen, swenson, swinson, syncom, syngman