cheerful

adjective

1. being full of or promoting cheer; having or showing good spirits

- her cheerful nature

- a cheerful greeting

- a cheerful room

Similar word(s): beaming, glad, beamish, smiling, twinkly, blithe, blithesome, lighthearted, lightsome, buoyant, chirpy, perky, cheery, gay, sunny, chipper, debonair, debonaire, jaunty, happy, glad

2. pleasantly (even unrealistically) optimistic

Similar word(s): optimistic, pollyannaish, upbeat