THESAURUS
purr
be in heaven, be pleased, beam, birr, bombilate, bombinate, boom, bum, burr, buzz, delight, die with delight, drone, feel happy, go into raptures, hum, joy, laugh, sing, smile, take great satisfaction, thrum, tread on air, whir, whiz
ROGET THESAURUS
purr
Roll
N
roll, drumming, berloque, bombination, rumbling, tattoo, drumroll, dingdong, tantara, rataplan, whirr, ratatat, ratatat-tat, rubadub, pitapat, quaver, clutter, charivari, racket, cuckoo, repetition, peal of bells, devil's tattoo, reverberation, clickety-clack, hum,
purr, hummingbird, cat, kitten (animal sounds), rolling, monotonous, like a bee in a bottle.
Ululation
VB
cry, roar, bellow, blare, rebellow, growl, snarl, bark, bow-wow, yelp, bay, bay at the moon, yap, yip, yipe, growl, yarr, yawl, snarl, howl, grunt, gruntle, snort, squeak neigh, whinny, bray, mew, mewl, meow,
purr, caterwaul, pule, baa, bleat, low, moo, troat, croak, peep, coo, gobble, quack, honk, gaggle, guggle, crow, caw, squawk, screech cackle, cluck, clack, chuck, chuckle, hoot, hoo, chirp, cheep, chirrup, twitter, cuckoo, warble, trill, tweet, pipe, whistle, hum, buzz, hiss, blatter, ratatat.