Definition

Verb (phrasal verb): 1. To inform against someone; to report someone's misdeeds to an authority. 2. To have a noticeable, often negative, effect or impact on someone or something; to strain or wear down.

Usage

• Sense 1 (Informing): Used when someone reveals another person's secret or wrongdoing, typically to a person in authority (e.g., a teacher, parent, boss).
• Sense 2 (Affecting): Used to describe how something causes a visible or physical toll, often from prolonged use or stress.

Examples

• Sense 1 (Informing):
  • He didn't want to tell on his friend, but cheating was against the rules.
  • If you don't share the toy, I'm going to tell on you to Mom!
• Sense 2 (Affecting):
  • The years of hard labor began to tell on his health.
  • The stress of the job is starting to tell on her; she looks exhausted.

Advanced Usage

• The phrasal verb is separable. A pronoun object must come between "tell" and "on" (e.g., ). A noun object can come between or after (e.g., or ).
• In the "affecting" sense, it is not separable. The subject causing the effect comes before the phrasal verb, and the person/thing affected comes after "on."

Variants and Related Words

• Inform on/against (someone): A more formal synonym for the first sense.
• Snitch (on someone) / Rat (someone out): Informal, often derogatory synonyms for the first sense.
• Take a toll on (someone/something): A common synonym for the second sense.

Synonyms

• For Sense 1: inform on, report, betray, squeal on (slang), grass on (UK slang).
• For Sense 2: affect, impact, strain, wear on, take a toll on.

Related Phrasal Verbs

• Tell off: To reprimand or scold someone angrily.
  • The teacher told him off for talking in class.
• Tell apart: To distinguish between two or more similar things or people.
  • The twins are identical; I can't tell them apart.

Related Idioms

• Tell tales (out of school): To reveal secrets or gossip, similar to the first sense of "tell on."
  • Don't trust him; he's always telling tales.

Verb

1. produce an effect or strain on somebody
   • Each step told on his tired legs
2. give away information about somebody
   • He told on his classmate who had cheated on the exam