infra-sónico
See also: infrasónico
Portuguese edit
Adjective edit
infra-sónico (feminine infra-sónica, masculine plural infra-sónicos, feminine plural infra-sónicas)
- (European Portuguese) Pre-reform spelling (until 1990) of infrassónico. Still used in countries where the agreement hasn't come into effect; may occur as a sporadic misspelling.