China 
Africa 
- Qubit
- Queen post
- Quenching
- Quercetin
- Query
- Query expansion
- Query language
- Query optimization
- Query plan
- Query rewriting
- Query string
- Question answering
- Questionnaire
- Queue number
- Queueing theory
- Queues
- Queuing delay
- Quick clay
- Quick reference handbook
- QuickTime
- Quickhull
- Quicksand
- Quicksilver
- Quicksort
- Quiescent current
- Quiet areas
- Quinaldine
- Quinazoline
- Quinazolinone
- Quinic acid
- Quinine
- Quinoid
- Quinoline
- Quinone
- Quinoxaline
- Quintic equation
- Quoins
- Quorum sensing
- Quota sampling
- Quotient
- Quotient groups
- Quotient ring
- Quotient rule
- Qutrit
- R
- R*-tree
- R+ tree
- R-134a
- R-407C
- R-410A
- RERAM
- RF CMOS
- RF MEMS
- RF circuit
- RF front end
- RF module
- RF power amplifier
- RF probe
- RF switches
- RFC
- RFCs
- RFIC
- RFID
- RFLP
- RFM
- RFNA
- RFP
- RGD motif
- RGGI
- RHA
- RHEED
- RHU
- RHex
- RINEX
- RIP
- RIS
- RISC
- RIXS
- RKHS
- RL
- RL circuit
- RLC circuit
- RLE
- RLWE
- RMS
- RMSD
- RNA
- RNA Integrity Number
- RNA editing
- RNA hydrolysis
- RNA polymerase
- RNA polymerase II
- RNA silencing
- RNA structure
- RNA viruses
- RNA-binding proteins
- RNA-seq
- RNAV
- RNAi
- RNFL