英语词源字典 - 在线词源网站

caller (n.)[caller 词源字典]: c. 1500, "one who proclaims," agent noun from call (v.). Meaning "one who announces step changes at a dance" is recorded from 1882; "one who places a telephone call," 1898. Meaning "a social visitor" is attested from 1786.[caller etymology, caller origin, 英语词源]
pager (n.): "device that emits a signal when activated by a telephone call," 1968, agent noun from page (v.1).
person (n.): early 13c., from Old French persone "human being, anyone, person" (12c., Modern French personne) and directly from Latin persona "human being, person, personage; a part in a drama, assumed character," originally "mask, false face," such as those of wood or clay worn by the actors in later Roman theater. OED offers the general 19c. explanation of persona as "related to" Latin personare "to sound through" (i.e. the mask as something spoken through and perhaps amplifying the voice), "but the long o makes a difficulty ...." Klein and Barnhart say it is possibly borrowed from Etruscan phersu "mask." Klein goes on to say this is ultimately of Greek origin and compares Persephone.

Of corporate entities from mid-15c. The use of -person to replace -man in compounds and avoid alleged sexist connotations is first recorded 1971 (in chairperson). In person "by bodily presence" is from 1560s. Person-to-person first recorded 1919, originally of telephone calls.
tap (n.3): "device to listen in secretly on telephone calls," 1923, from tap (v.2) in the "listen secretly" sense.
on-hook: "(Of a telephone) having the receiver resting on the hook; chiefly in on-hook dialling, a facility for initiating a telephone call without lifting the receiver", 1970s; earliest use found in The New York Times.