From Longman Dictionary of Contemporary Englishtell against somebody phrasal verb British English formalADVANTAGEto make someone less likely to succeed in achieving or winning something I badly wanted the job, but knew that my age would probably tell against me. → tell→ See Verb table
Examples from the Corpus
tell against • He's 26 or 27 now and that final year of waiting to qualify could tell against him.• My favourite is one tale Prost tells against himself.• On the contrary they tell against it.• There is a story told against Jimmy Davidson which, in fact, should be told against the game in Ireland.• Turning to the evidence, he stressed those aspects of it which told against Meehan and in favour of Waddell.• Obviously, if the alternative offer had involved a considerably or prohibitively higher price, that would tell against the seller. 