bi

Everyday

1. (prefix) Two or twice, as in bicycle (two wheels), bilingual (two languages), biannual (twice a year). tree →
2. (informal) Short for bisexual: attracted to more than one gender. tree →
3. Short for "bye" in some texting (bi or bai — slang). tree →

In the lessons

In maths and science the prefix helps you guess meanings: bisect (cut into two equal parts), biped (two-footed animal), binary (base two). In everyday talk, "bi" is a short label for bisexual. Phrases: bi-weekly, bi-monthly.

Examples

• A bicycle has two wheels. tree →
• Bisect the angle with your compass. tree →
• She is bilingual: she speaks English and Welsh. tree →
• Birds are bipeds because they walk on two legs. tree →
• Binary numbers use only 0 and 1. tree →
• He told his friends he is bi. tree →

Note

Trap: bi-weekly and bi-monthly can mean "every two" OR "twice a" — check which. Biannual = twice a year; biennial = every two years. "Bi" alone is informal; not an insult.

In Jewish tradition

In maths and science the prefix helps you guess meanings: bisect (cut into two equal parts), biped (two-footed animal), binary (base two). In everyday talk, "bi" is a short label for bisexual. Phrases: bi-weekly, bi-monthly.

Examples

• ") See Nestle in Hasting's Bi/i/e Diclionnry, vol IV, p 542. (Mordell, The Origin of Letters and Numerals according to Sefer Yetzirah (1914)) tree →
• And David said to Joab, and to all the people that were with him: 'Rend your clothes, and gird you with sackcloth, and wail before Abner.' And king David followed the bier. (Prophets 2SA.3.31, JPS 1917) tree →

Note

Trap: bi-weekly and bi-monthly can mean "every two" OR "twice a" — check which. Biannual = twice a year; biennial = every two years. "Bi" alone is informal; not an insult.