Definitions

1. adverb

in a sidelong manner; obliquely; indirectly

“He looked at her sidelong, trying not to make eye contact.”

2. noun

a glance or look in a sidelong manner

“She caught his sidelong glance and felt self-conscious.”

3. adjective

given to or characterized by glancing or looking obliquely

“The sidelong gaze of the cat was unsettling.”