Semiannually rhymes with:
annually, conceptually, continually, contractually, factually, gradually, habitually, individually, intellectually, manually, mutually, perpetually, sexually, virtually
Semiannually sounds like:
saemaul, samella, samelle, samuel, samuela, samuelle, sawmill, scammell, scannell, schamel, schemel, schemmel, schenley, schimmel, schmahl, schmal, schmale, schmall, schmehl, schmoll, schmuhl, schnall, schnell, schnelle, seasonal, seasonally, seemala, semel, semele, semiannual, seminal, seminole, semmel, senile, shamalia, shamel, shamelle, shanley, shemwell, shimel, shimmel, shinall, siemel, signal, simonelli, smail, smale, small, smalley, smeal, smell, smelley, smelly, smile, smiley, smilie, smillie, smilow, smola, smoley, smull, smylie, smyly, snail, snell, somali, somalia, suchomel, sunil, synalloy