To tend means to take care of something or someone regularly. A gardener tends flowers by watering them, pulling weeds, and making sure they get enough sunlight. A nurse tends to patients by checking their condition and helping them feel more comfortable. When you tend to a pet, you feed it, give it water, and keep it healthy.

The word suggests ongoing attention rather than a one-time action. You don't just water a garden once and forget it: you tend it day after day, watching how it grows and responding to what it needs. A shepherd tends sheep by watching over them constantly, guiding them to good grazing areas and protecting them from danger.

Tend also means to be likely to do something or have a habit of doing it. If you tend to forget your homework when you're tired, that means it happens often enough to be a pattern. Some dogs tend to bark at strangers, while others tend to greet everyone happily. Scientists might observe that certain chemicals tend to react in predictable ways under specific conditions. This meaning captures how things naturally lean or incline in a particular direction: “She tends toward optimism” means optimism is her natural inclination.