Synonyms for Handler:

n.

baron, ambassador, boss, account executive, businesswoman, administrator, businessperson, businessman, capitalist, agent. domesticate, kitty litter, kennel, answer to, call off, exercise, heel, cat litter, litter. clip art, field, autoflow, bug, browse mode, clipboard, autosave, automatic hyphenation, file format, edit. consignment, freight, cargo, carrier, dock, bill of entry, bill of lading, delivery. agent (noun)
ambassador.
handler (noun)
coach, manager, animal trainer.
manager (noun)
boss, administrator.
merchant (noun)
businessperson.
trainer (noun)
coach.

Other synonyms:

kitty litter, cat litter, kennel, domesticate, litter. heel. answer to. exercise. Other relevant words:
carrier, litter, boss, agent, kennel.