Definition

Relating to the movement of organisms in response to light.

Example

Certain insects are phototactic, moving towards light sources.

Conversation

Did you know that some insects are phototactic?

Really? What does that mean exactly?

It means they are attracted to light, especially at night.

That’s interesting! I guess that’s why they always buzz around lamps.

Synonyms & Antonyms

Root Explanation

Phototactic → It is formed from "photo-" (from Greek "phōs", meaning light) and "tactic" (from Greek "taktikos", meaning relating to arrangement or order). The word "phototactic" refers to the movement of an organism in response to light, indicating how it arranges itself in relation to light sources.

Memory Tip

Think of 'light' ('photo-') guiding the 'arrangement' ('tactic') of an organism's movement — that's why phototactic means moving in response to light.

Visually Confused Words