alternate; alternating; mutual; reciprocal
equal (in ability); even; evenly matched; well-matched; on par (with)
alternately; by turns; one after the other
downward compatible; backward compatible; compatible with input or components intended for lower tier or older systems, versions, etc.; upward compatible; forward compatible; compatible with input or components intended for higher tier or later systems, versions, etc.
interchange; transposition; compatible (e.g. PC)
upward compatible; forward compatible; compatible with input or components intended for higher tier or later systems, versions, etc.; downward compatible; backward compatible; compatible with input or components intended for lower tier or older systems, versions, etc.
mutual aid; cooperation; benefit
mutual relationship; interrelationship; interaction
(mutual) interaction; reciprocal action; interplay
intercommunication (usu. in telecoms contexts)
mutual assured destruction
election by mutual vote; election from within a committee (party, etc.); internal vote
alternate (esp. of leaf arrangement)
mutual use of company facilities (e.g. rail tracks for through service, airport facilities, code-sharing, etc.)
cross connection; interconnection; internetworking
reciprocal relationship; mutually beneficial relations; relationship with benefits to both parties
reciprocity; mutual benefit
equal contest; close game; well-matched game; even match
give and take; mutual concession; conciliation; compromise
backward compatible; downward compatible
backward compatibility; downward compatibility
fundamental interaction (i.e. gravitation, electromagnetism, weak interaction, strong interaction)
to strive for mutual understanding
electromagnetic interaction
open account; running account; current account; mutual account
forward compatible; upward compatible
forward compatibility; upward compatibility
baryon-baryon interaction
downward compatibility; backward compatibility; compatibility with input or components intended for lower tier or older systems, versions, etc.; upward compatibility; forward compatibility; compatibility with input or components intended for higher tier or later systems, versions, etc.
gravitational interaction
fundamental interaction; fundamental force
Open Systems Interconnection; OSI
HATS; Harmonization of Advanced Telecommunication Systems
interoperability test, study
open systems interconnection environment
upward compatibility; forward compatibility; compatibility with input or components intended for higher tier or later systems, versions, etc.; downward compatibility; backward compatibility; compatibility with input or components intended for lower tier or older systems, versions, etc.
interconnection; interoperability
law of quadratic reciprocity
basic interconnection tests
transinformation (content); transferred information; transmitted information; mutual information
strategic reciprocity; mutually beneficial relationship based on common strategic interests
interconnection test; interoperability test
mutual visitation; reciprocal visits
using together; using in turn
interchangeability; interoperability
cross-referencing indication
electromagnetic compatibility
reciprocal treaty; treaty of reciprocity
training by participants of the same skill level (kendo)
binary level compatibility
compatibility test; interoperability test