A whistle lisp is defined by producing a slight whistling noise when pronouncing words beginning with "s" or "sh". Most noticible when conversing with elderly gay men with possible dental or identity issues.
Mr. Herbert ssssssaid that SSSSSweet SSSSSam'sssssss sssssalute wasssssss ssssssloppy and sssssaucy. He sssssent Ssssssam sssssstateside to practicccccccce that sssssssaucy sssssalute. These words all have a whistle lisp.