pat1
verb
Brian patted her absent-mindedly on the shoulder:
tap, slap lightly, clap, dab;
touch, stroke, pet, caress, fondle, rub.
noun
2 a pat of butter:
piece, dab, lump, portion, knob, mass, cake, chunk, wedge, hunk, ball, curl;
British gobbet;
rare clod, gob.
□ a pat on the back
you owe me a pat on the back for a job well done:
praise, congratulations, commendation, applause, salutes, honour, acclaim, acclamation, tribute, cheers, ovation, accolade, plaudits, felicitations;
approval, admiration, approbation, compliments, kudos, adulation, homage;
eulogy, encomium, panegyric, bouquets, laurels, testimonial;
rare extolment, laudation, eulogium.
pat (1) Oxford Dictionary of English