осно́ва

• noun
• Level B1
• Rank 646 of 12,000
• 0.022% of running text

basis, base, foundation

Recording: Wikimedia Commons

• proper noun
• Level B1
• Rank 11,670 of 12,000
• 0.001% of running text

Meanings

1. stem (linguistics: main part of a word)
2. basis, base, foundation
3. foundation (that upon which anything is founded)
4. (chemistry) base

female, inanimate

The dictionary keeps one entry for the spelling основа, so these meanings cover every use above.