person

Ma-Pa

also: Ма-Па

A household nickname -- most likely for Chekhov's sister Maria Pavlovna, whose initials the name compresses -- for the 'most amiable' companion who goes with Chekhov to have photographs taken, he to sell his to admirers, she to hand hers out to suitors.

Reading notes

To M. V. Kiseleva, 13 September 1887. Moscow. §10 the most amiable Ma-Pa
A household nickname, most likely for Chekhov's sister Maria Pavlovna ("Ma-Pa" compressing her initials), who joins him to have photographs taken -- his for admirers of his growing literary fame, hers for suitors.
To M. V. Kiseleva, 28 September 1887. Moscow. §11 Ma-Pa
Household nickname, most likely for Chekhov's sister Maria Pavlovna, who reports the sighting of Mlle Syrout that follows.
To M. V. Kiseleva, 3 February 1888. Moscow. §10 Ma-Pe
"Ma-Pe" is the same household nickname elsewhere spelled "Ma-Pa", most likely for Chekhov's sister Maria Pavlovna; Kiseleva had apparently written to her praising Chekhov's "prudence," which he now professes baffled indignation at.
To A. S. Kiselev, 15 February 1888. Moscow. §6 Ma-Pa and Finik
"Ма-Па и Финик" are two household nicknames for members of Chekhov's own sibling circle (Ma-Pa most likely his sister Maria Pavlovna, as elsewhere in these letters; Finik a sibling nickname not securely identifiable) -- distinct from "мать и батька" ("Mother and Father"), his actual parents, named two sentences later. The two pairs are being explicitly contrasted, not conflated: the siblings lean toward summering at Babkino, while the parents dream of a trip to their native Ukraine ("Khokhlandia"). Note also that "Finik" here is unrelated to the character "Bogemsky, otherwise known as Finik" nicknamed in a different letter; the two are separate individuals who happen to share a household nickname.