2. Adjective. Similar to a weasel ¹
3. Adjective. Similar to that of a weasel; as, a weasellike face ¹
4. Adjective. (figuratively) underhanded(2); shady(4) ¹
5. Adverb. (alternative spelling of weasel-like) ¹
6. Adverb. In the manner of a weasel. ¹
¹ Source: wiktionary.com