From Longman Dictionary of Contemporary Englishspeakerphonespeak‧er‧phone /ˈspiːkəfəʊn $ -kərfoʊn/ noun [countable] especially American English a telephone that contains a microphone and a loudspeaker, so that you can use it without holding it. Speakerphones are especially used in business meetings when groups of people in different places want to talk to each other.
Examples from the Corpus
speakerphone• Both computers had a 28,800-baud fax modem, 16 megabytes of random-access memory and voice mail / speakerphone capabilities.• A technician using the speakerphone will ask which of his residents you wish to view.From Longman Business Dictionaryspeakerphonespeak‧er‧phone /ˈspiːkəfəʊn-kərfoʊn/ noun [countable]OFFICE a telephone that you can use without holding it near your face, so that a small group of people can hear and take part in the conversationa handsfree speakerphone with digital sound enhancement 