Synonyms for Telling:

adj.

effective (adjective)
cogent.
effective, significant (adjective)
effectual, conspicuous, important, impressive, convincing, valid, satisfactory, weighty, forceful, devastating, cogent, crucial.
important (adjective)
key, vital, crucial, major, serious, central, fundamental, meaningful.
persuasive (adjective)
convincing.

n.

representational, unambiguous, indicative, symbolic, illocutionary, expressive, well-defined. satisfactory, convincing, persuasive, persuasion. crucial (noun)
study at valid, significant, conspicuous, devastating, valid, important.
report (noun)
log, description, monograph, account, portrayal, history, statement, article, diary, anecdote, record, report, recounting, table, journal, summary, memoir, narrative, retelling, treatise, chronicle.
telling (noun)
informatory, revealing, singing, forceful, informative, efficacious, notification, tattle, relation, impressive, effective, recounting, telltale, weighty, effectual, cogent, apprisal.

v.

reporting (verb)
Chronicling, logging, Journalizing, Narrating, portraying, Stating, Tabling, summarizing, Describing, reporting, accounting, recording.

Other synonyms:

illocutionary, symbolic, valid, unambiguous. persuasive, significant, representational, convincing, indicative. meaningful. satisfactory. eloquent
expressive.
Other relevant words:
informatory, well-defined, persuasive, persuasion, major, crucial, singing, central, notification, revealing, devastating, impressive, expressive, cogent, forceful, satisfactory, vital, relation, representational, informative, efficacious, symbolic, unambiguous, apprisal, meaningful, tattle, conspicuous, effectual, effective, telltale, convincing, illocutionary, weighty, valid, serious, key, indicative, fundamental, significant, important.

Usage examples for telling

  1. To Ellerton he meant to give such a telling off as the young man had never heard in his life before. – The Disturbing Charm by Berta Ruck
  2. Oh, you are not telling me the truth! – Castle Craneycrow by George Barr McCutcheon
  3. True, it was very telling – Our Bessie by Rosa Nouchette Carey