Longman Dictionary of Contemporary English
small ad
noun
EXAMPLES FROM CORPUS
▪ MI6 placed a small ad in a newspaper to retrieve a laptop containing state secrets after it was lost by an agent.
Wiktionary
small ad
n. small, simple advertisement in newspaper or magazine, usually collected in a section.
Usage examples of "small ad".
To get clients he ran a perpetual small ad in _Ceramics Monthly_ .