Darren Bravo's unbeaten 72 piloted the home team to victory, the left-hander earning both the man-of-the-match and man-of-the-series awards following on his maiden ODI hundred in the first match on Friday.
Kieran Powell contributed 42 at the top of the order while the effort of young wrist-spinners Natsai M'Shangwe and debutant Tinotenda Mutombodzi offered some encouragement for the Zimbabweans ahead of the two T20 fixtures to be played at the weekend in Antigua.
Mutombodzi removed Ramnaresh Sarwan caught-and-bowled with just his third delivery in senior international cricket and also accounted for Powell to a catch at long-on.
There were a few moments of anxiety for the West Indies when the dismissal of Narsingh Deonarine by Hamilton Masakadza was followed by the running out of Kieron Pollard for a duck without facing a ball to leave the home side at 121 for four.
"I just went out there and backed my ability and it was good to be part of another West Indies victory," said Darren Bravo, who acknowledged his role in Pollard's swift demise.
"I want to apologise to Kieron for running him out because I probably deprived the crowd of some entertainment."
Skipper Dwayne Bravo steadied the innings in partnership with his younger brother and it was left to wicketkeeper-batsman Denesh Ramdin to accompany Darren Bravo at the crease when the winning runs were struck, the captain falling to Kyle Jarvis with the result virtually assured.
"This was a special result for us as we want to dedicate it to one our legends of West Indies cricket, Sir Everton Weekes," said the team leader after the match, acknowledging the 88th birthday of one of the West Indies' greatest-ever batsmen.
"I've got to give credit to our opening bowlers, Kemar Roach and Tino Best, because they set the tone for the others to follow."
Disciplined work by the West Indies in the field had restricted Zimbabwe to 211 for nine after the visitors chose to bat first again.
The home side's bowlers kept wayward deliveries to a minimum and reaped the reward against the Zimbabweans, a couple of whom got decent starts but weren't able to carry on as occurred in the second ODI on Sunday when three got past the 50-run mark.
Chamu Chibhabha, strangely demoted to number seven in the order, gave the innings some respectability with an unbeaten 48, his side's top score.
Playing his first match of the series in place of all-rounder Andre Russell, left-arm spinner Veerasammy Permaul was the most successful of the Caribbean bowlers, claiming three for 40 off his 10-over allotment.
His dismissal of Zimbabwean captain Brendan Taylor (39) proved crucial in stalling the tourists' efforts and the Guyanese player added the wickets of Malcolm Waller and Regis Chakabva to complete a satisfying morning's work.
At the top of the order, Vusi Sibanda promised a substantial innings, but yet again failed to carry on from a good start, falling to fast bowler Tino Best for 41.
"It's not acceptable. We've all played enough cricket and should be batting through as the West Indian guys have done," was Taylor's lament at the failure of the Zimbabwean batsmen, including himself, to play the big innings.