Where does “pet regression” come from?

pet regression (English) comes from English PET, from English petition, from Old French peticiun, from Latin petitio, from Latin -tiō, from Latin dissertātiō, from Latin dissertus, from Latin disserere — small stone, pebble; gravel, rubble.

pet regression (English): The state in which a person temporarily adopts the mindset of, or roleplays as, an animal, especially when done as coping mechanism to relieve stress, anxiety or trauma, or simply for recreational entertainment (for fun); the state in which one enters the headspace of an animal

Definitions

  1. The state in which a person temporarily adopts the mindset of, or roleplays as, an animal, especially when done as coping mechanism to relieve stress, anxiety or trauma, or simply for recreational entertainment (for fun); the state in which one enters the headspace of an animal

Ancestry of “pet regression”, step by step

pet regression traces back through two separate lines of ancestry.

via English PET

StepLanguageWordMeaning
1EnglishPETInitialism of polyethylene terephthalate; Acronym...
2EnglishpetitionA formal, written request made to an official...
3Old Frenchpeticiunrequest; demand
4Latinpetitioan attack, thrust, blow; a request, petition,...
5Latin-tiōtion, -ation, -ing
6Latindissertātiō(spoken) dissertation, discourse, disquisition
7Latindissertusarranged, disposed; explained
8Latindissereresecond-person singular future passive indicative...
9Latindis-asunder, apart, in two; reversal, removal;...
10Latincalceusshoe
11Latincalxlimestone; chalk; the finish line
12Ancient Greekχάλιξsmall stone, pebble; gravel, rubble

via English regression

StepLanguageWordMeaning
1EnglishregressionAn action of regressing, a return to a previous...
2Latinregressusreturned, having returned; retired, retreated,...
3LatinregrediorI go or come back; turn back, return; I march...
4Latinrĕ-back, backwards
5Latinprōdūcōto lead or bring forth, forward or out
6Latinprō-forward direction, forward movement
7Proto-Italic*pro-pro- see the Latin entry for further meanings
8Proto-Indo-Europeanpro-toward, forward
9Proto-Indo-Europeanpor-to give birth; forward, through; going, passage
10Proto-Indo-Europeanper-before, in front; first; to go through
11Proto-Indo-Europeanpr̥tóspassed , crossed
Every word from Ancient Greek χάλιξEvery word from Latin -tiōEvery word from Latin dis-
pet regression — Etymology, Origin & Word History | Etymology Explorer