(jargon) The practice of engaging in anal sex with the deliberate intention of contracting HIV.

(gay slang) A man who practises bug-chasing.

A firefly.

(computing) A design flaw in computer systems that represented years as two digits (e.g. 84 for 1984), which could cause date calculations to fail if they involved years later than 1999.

Any of various shield-shaped true bugs of the superfamily Pentatomoidea.

Any of various insects of the order Hemiptera and in particular of the suborder Heteroptera, that are wingless or have two pairs of wings, and have mouthparts adapted for piercing and sucking.

(US) an insect, of the family Lygaeidae, that mostly feeds on the seeds and tissue of the milkweed plant (Asclepias).

the millennium bug

An insecticide for killing household pests. / Insect repellent.

Alternative spelling of ladybug